Rewrote the updater system from scratch

Change-Id: Ia92ef9058621aa0a3cb67dc1fb30a13642580303
Depends-On: Iab5db6ba7738102fbe45e37670f6cfd3c705fd9c
Reviewed-on: http://gerrit.dmdirc.com/2381
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Greg Holmes <greg@dmdirc.com>

src/com/dmdirc/Main.java

@@ -110,6 +110,8 @@ public final class Main {
             handleInvalidConfigFile();
         }
 
+        UpdateChecker.init();
+
         MessageSinkManager.getManager().loadDefaultSinks();
 
         final PluginManager pm = PluginManager.getPluginManager();
@@ -144,8 +146,6 @@ public final class Main {
         ActionManager.getActionManager().triggerEvent(
                 CoreActionType.CLIENT_OPENED, null);
 
-        UpdateChecker.init();
-
         clp.processArguments();
 
         GlobalWindow.init();

src/com/dmdirc/updater/Update.java

@@ -1,239 +0,0 @@
-/*
- * Copyright (c) 2006-2012 DMDirc Developers
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package com.dmdirc.updater;
-
-import com.dmdirc.Main;
-import com.dmdirc.logger.ErrorLevel;
-import com.dmdirc.logger.Logger;
-import com.dmdirc.util.collections.WeakList;
-import com.dmdirc.util.io.DownloadListener;
-import com.dmdirc.util.io.Downloader;
-
-import java.io.IOException;
-import java.util.List;
-
-/**
- * Represents a single available update for some component.
- */
-public final class Update implements DownloadListener {
-
-    /** Update component. */
-    private final UpdateComponent component;
-    /** Remote version name. */
-    private final String versionName;
-    /** Update url. */
-    private final String url;
-    /** The progress of the current stage. */
-    private float progress;
-
-    /** A list of registered update listeners. */
-    private final List<UpdateListener> listeners
-            = new WeakList<UpdateListener>();
-
-    /** Our current status. */
-    private UpdateStatus status = UpdateStatus.PENDING;
-
-    /**
-     * Creates a new instance of Update, with details from the specified line.
-     *
-     * @param updateInfo An update information line from the update server
-     */
-    public Update(final String updateInfo) {
-        // outofdate client STABLE 20071007 0.5.1 file
-        final String[] parts = updateInfo.split(" ");
-
-        if (parts.length == 6) {
-            component = UpdateChecker.findComponent(parts[1]);
-            versionName = parts[4];
-            url = parts[5];
-        } else {
-            component = null;
-            versionName = null;
-            url = null;
-
-            Logger.appError(ErrorLevel.LOW,
-                    "Invalid update line received from server: ",
-                    new UnsupportedOperationException("line: " + updateInfo));
-        }
-    }
-
-    /**
-     * Retrieves a string representation of this update. The result from this
-     * method may be passed to the {@link Update} constructor to create a copy
-     * of the update.
-     *
-     * @since 0.6.5
-     * @return A string representation of this update
-     */
-    public String getStringRepresentation() {
-        return "outofdate " + component.getName()
-                + " CHANNEL versionNumber " + versionName + " " + url;
-    }
-
-    /**
-     * Retrieves the component that this update is for.
-     *
-     * @return The component of this update
-     */
-    public UpdateComponent getComponent() {
-        return component;
-    }
-
-    /**
-     * Returns the remote version of the component that's available.
-     *
-     * @return The remote version number
-     */
-    public String getRemoteVersion() {
-        return versionName;
-    }
-
-    /**
-     * Returns the URL where the new update may be downloaded.
-     *
-     * @return The URL of the update
-     */
-    public String getUrl() {
-        return url;
-    }
-
-    /**
-     * Retrieves the status of this update.
-     *
-     * @return This update's status
-     */
-    public UpdateStatus getStatus() {
-        return status;
-    }
-
-    /**
-     * Sets the status of this update, and notifies all listeners of the change.
-     *
-     * @param newStatus This update's new status
-     */
-    protected void setStatus(final UpdateStatus newStatus) {
-        status = newStatus;
-        progress = 0;
-
-        for (UpdateListener listener : listeners) {
-            listener.updateStatusChange(this, status);
-        }
-    }
-
-    /**
-     * Removes the specified update listener.
-     *
-     * @param o The update listener to remove
-     */
-    public void removeUpdateListener(final Object o) {
-        listeners.remove(o);
-    }
-
-    /**
-     * Adds the specified update listener.
-     *
-     * @param e The update listener to add
-     */
-    public void addUpdateListener(final UpdateListener e) {
-        listeners.add(e);
-    }
-
-    /**
-     * Makes this update download and install itself.
-     */
-    public void doUpdate() {
-        new Thread(new Runnable() {
-
-            /** {@inheritDoc} */
-            @Override
-            public void run() {
-                final String path = Main.getConfigDir() + "update.tmp."
-                        + Math.round(Math.random() * 1000);
-
-                setStatus(UpdateStatus.DOWNLOADING);
-
-                try {
-                    Downloader.downloadPage(getUrl(), path, Update.this);
-                } catch (IOException ex) {
-                    setStatus(UpdateStatus.ERROR);
-
-                    Logger.userError(ErrorLevel.MEDIUM,
-                            "Error when updating component "
-                            + component.getName(), ex);
-
-                    return;
-                }
-
-                setStatus(UpdateStatus.INSTALLING);
-
-                try {
-                    final boolean restart = getComponent().doInstall(path);
-
-                    if (restart) {
-                        setStatus(UpdateStatus.RESTART_NEEDED);
-                        UpdateChecker.removeComponent(getComponent().getName());
-                    } else {
-                        setStatus(UpdateStatus.INSTALLED);
-                    }
-                } catch (IOException ex) {
-                    setStatus(UpdateStatus.ERROR);
-                    Logger.userError(ErrorLevel.MEDIUM,
-                            "I/O error when updating component "
-                            + component.getName(), ex);
-                } catch (Exception ex) {
-                    setStatus(UpdateStatus.ERROR);
-                    Logger.appError(ErrorLevel.MEDIUM,
-                            "Error when updating component "
-                            + component.getName(), ex);
-                }
-            }
-
-        }, "Update thread").start();
-    }
-
-    /** {@inheritDoc} */
-    @Override
-    public void downloadProgress(final float percent) {
-        progress = percent;
-
-        for (UpdateListener listener : listeners) {
-            listener.updateProgressChange(this, percent);
-        }
-    }
-
-    /**
-     * Retrieves the current progress of the current state of this update.
-     *
-     * @return The percentage of the current stage that has been completed
-     */
-    public float getProgress() {
-        return progress;
-    }
-
-    /** {@inheritDoc} */
-    @Override
-    public void setIndeterminate(final boolean indeterminate) {
-        //TODO
-    }
-
-}

src/com/dmdirc/updater/UpdateChecker.java

@@ -22,92 +22,40 @@
 
 package com.dmdirc.updater;
 
-import com.dmdirc.Precondition;
+import com.dmdirc.Main;
 import com.dmdirc.config.ConfigManager;
 import com.dmdirc.config.IdentityManager;
 import com.dmdirc.logger.ErrorLevel;
 import com.dmdirc.logger.Logger;
-import com.dmdirc.updater.components.ClientComponent;
-import com.dmdirc.updater.components.DefaultsComponent;
-import com.dmdirc.updater.components.ModeAliasesComponent;
-import com.dmdirc.util.collections.ListenerList;
-import com.dmdirc.util.io.Downloader;
+import com.dmdirc.updater.manager.CachingUpdateManager;
+import com.dmdirc.updater.manager.DMDircUpdateManager;
+import com.dmdirc.updater.manager.UpdateStatus;
 
-import java.io.IOException;
-import java.net.MalformedURLException;
-import java.util.ArrayList;
 import java.util.Date;
-import java.util.List;
 import java.util.Timer;
 import java.util.TimerTask;
 import java.util.concurrent.Semaphore;
 
+import lombok.Getter;
+
 /**
  * The update checker contacts the DMDirc website to check to see if there
  * are any updates available.
  */
 public final class UpdateChecker implements Runnable {
 
-    /** The possible states for the checker. */
-    public static enum STATE {
-        /** Nothing's happening. */
-        IDLE,
-        /** Currently checking for updates. */
-        CHECKING,
-        /** Currently updating. */
-        UPDATING,
-        /** New updates are available. */
-        UPDATES_AVAILABLE,
-        /** Updates installed but restart needed. */
-        RESTART_REQUIRED,
-    }
-
     /** The domain to use for updater settings. */
     private static final String DOMAIN = "updater";
 
     /** Semaphore used to prevent multiple invocations. */
     private static final Semaphore MUTEX = new Semaphore(1);
 
-    /** A list of components that we're to check. */
-    private static final List<UpdateComponent> COMPONENTS
-            = new ArrayList<UpdateComponent>();
-
     /** Our timer. */
     private static Timer timer = new Timer("Update Checker Timer");
 
-    /** The list of updates that are available. */
-    private static final List<Update> UPDATES = new ArrayList<Update>();
-
-    /** A list of our listeners. */
-    private static final ListenerList LISTENERS = new ListenerList();
-
-    /** Our current state. */
-    private static STATE status = STATE.IDLE;
-
-    /** A reference to the listener we use for update status changes. */
-    private static final UpdateListener LISTENER = new UpdateListener() {
-        @Override
-        public void updateStatusChange(final Update update, final UpdateStatus status) {
-            if (status == UpdateStatus.INSTALLED
-                || status == UpdateStatus.ERROR) {
-                removeUpdate(update);
-            } else if (status == UpdateStatus.RESTART_NEEDED && UpdateChecker.status
-                    == STATE.UPDATING) {
-                doNextUpdate();
-            }
-        }
-
-        @Override
-        public void updateProgressChange(final Update update, final float progress) {
-            // Don't care
-        }
-    };
-
-    static {
-        COMPONENTS.add(new ClientComponent());
-        COMPONENTS.add(new ModeAliasesComponent());
-        COMPONENTS.add(new DefaultsComponent());
-    }
+    /** The update manager to use. */
+    @Getter
+    private static CachingUpdateManager manager;
 
     /** {@inheritDoc} */
     @Override
@@ -120,8 +68,7 @@ public final class UpdateChecker implements Runnable {
 
         final ConfigManager config = IdentityManager.getIdentityManager().getGlobalConfiguration();
 
-        if (!config.getOptionBool(DOMAIN, "enable")
-                || status == STATE.UPDATING) {
+        if (!config.getOptionBool(DOMAIN, "enable")) {
             IdentityManager.getIdentityManager().getGlobalConfigIdentity().setOption(DOMAIN,
                     "lastcheck", String.valueOf((int) (new Date().getTime() / 1000)));
 
@@ -130,64 +77,7 @@ public final class UpdateChecker implements Runnable {
             return;
         }
 
-        setStatus(STATE.CHECKING);
-
-        // Remove any existing update that isn't waiting for a restart.
-        for (Update update : new ArrayList<Update>(UPDATES)) {
-            if (update.getStatus() != UpdateStatus.RESTART_NEEDED) {
-                UPDATES.remove(update);
-            }
-        }
-
-        final StringBuilder data = new StringBuilder();
-        final String updateChannel = config.getOption(DOMAIN, "channel");
-
-        // Build the data string to send to the server
-        for (UpdateComponent component : COMPONENTS) {
-            if (isEnabled(component)) {
-                data.append(component.getName());
-                data.append(',');
-                data.append(updateChannel);
-                data.append(',');
-                data.append(component.getVersion());
-                data.append(';');
-            }
-        }
-
-        // If we actually have components to check
-        if (data.length() > 0) {
-            try {
-                final List<String> response
-                    = Downloader.getPage("http://updates.dmdirc.com/", "data=" + data);
-
-                for (String line : response) {
-                    checkLine(line);
-                }
-            } catch (MalformedURLException ex) {
-                Logger.appError(ErrorLevel.LOW, "Error when checking for updates", ex);
-            } catch (IOException ex) {
-                Logger.userError(ErrorLevel.LOW,
-                        "I/O error when checking for updates: " + ex.getMessage());
-            }
-        }
-
-        if (UPDATES.isEmpty()) {
-            setStatus(STATE.IDLE);
-        } else {
-            boolean available = false;
-
-            // Check to see if the updates are outstanding or just waiting for
-            // a restart
-            for (Update update : UPDATES) {
-                if (update.getStatus() == UpdateStatus.PENDING) {
-                    available = true;
-                }
-            }
-
-            setStatus(available ? STATE.UPDATES_AVAILABLE : STATE.RESTART_REQUIRED);
-        }
-
-        updateCachedUpdates();
+        manager.checkForUpdates();
 
         MUTEX.release();
 
@@ -197,67 +87,17 @@ public final class UpdateChecker implements Runnable {
         UpdateChecker.initTimer();
 
         if (config.getOptionBool(DOMAIN, "autoupdate")) {
-            applyUpdates();
-        }
-    }
-
-    /**
-     * Updates the cache of pending updates in the configuration file.
-     *
-     * @since 0.6.5
-     */
-    private static void updateCachedUpdates() {
-       final List<String> stringCopies = new ArrayList<String>();
-
-        for (Update update : UPDATES) {
-            // Only include outstanding updates
-            if (update.getStatus() == UpdateStatus.PENDING
-                    || update.getStatus() == UpdateStatus.ERROR) {
-                stringCopies.add(update.getStringRepresentation());
+            for (UpdateComponent component : manager.getComponents()) {
+                if (manager.getStatus(component) == UpdateStatus.UPDATE_PENDING) {
+                    manager.install(component);
+                }
             }
-        }
-
-        IdentityManager.getIdentityManager().getGlobalConfigIdentity()
-                .setOption(DOMAIN, "updates", stringCopies);
-    }
-
-    /**
-     * Checks the specified line to determine the message from the update server.
-     *
-     * @param line The line to be checked
-     */
-    private static void checkLine(final String line) {
-        if (line.startsWith("outofdate")) {
-            doUpdateAvailable(line);
-        } else if (line.startsWith("error")) {
-            String errorMessage = "Error when checking for updates: " + line.substring(6);
-            final String[] bits = line.split(" ");
-            if (bits.length > 2) {
-                final UpdateComponent thisComponent = findComponent(bits[2]);
-
-                if (thisComponent instanceof FileComponent) {
-                    errorMessage = errorMessage + " (" + ((FileComponent) thisComponent)
-                            .getFileName() + ")";
+        } else if (config.getOptionBool(DOMAIN, "autodownload")) {
+            for (UpdateComponent component : manager.getComponents()) {
+                if (manager.getStatus(component) == UpdateStatus.UPDATE_PENDING) {
+                    manager.retrieve(component);
                 }
             }
-            Logger.userError(ErrorLevel.LOW, errorMessage);
-        } else if (!line.startsWith("uptodate")) {
-            Logger.userError(ErrorLevel.LOW, "Unknown update line received from server: "
-                    + line);
-        }
-    }
-
-    /**
-     * Informs the user that there's an update available.
-     *
-     * @param line The line that was received from the update server
-     */
-    private static void doUpdateAvailable(final String line) {
-        final Update update = new Update(line);
-
-        if (update.getUrl() != null) {
-            UPDATES.add(update);
-            update.addUpdateListener(LISTENER);
         }
     }
 
@@ -266,14 +106,8 @@ public final class UpdateChecker implements Runnable {
      * frequency specified in the config.
      */
     public static void init() {
-        for (String update : IdentityManager.getIdentityManager()
-                .getGlobalConfiguration().getOptionList(DOMAIN, "updates")) {
-            checkLine(update);
-        }
-
-        if (!UPDATES.isEmpty()) {
-            setStatus(STATE.UPDATES_AVAILABLE);
-        }
+        manager = new DMDircUpdateManager(IdentityManager.getIdentityManager()
+                .getGlobalConfiguration(), Main.getConfigDir(), 3);
 
         initTimer();
     }
@@ -320,172 +154,4 @@ public final class UpdateChecker implements Runnable {
         new Thread(new UpdateChecker(), "Update Checker thread").start();
     }
 
-    /**
-     * Registers an update component.
-     *
-     * @param component The component to be registered
-     */
-    public static void registerComponent(final UpdateComponent component) {
-        COMPONENTS.add(component);
-    }
-
-    /**
-     * Unregisters an update component with the specified name.
-     *
-     * @param name The name of the component to be removed
-     */
-    public static void removeComponent(final String name) {
-        UpdateComponent target = null;
-
-        for (UpdateComponent component : COMPONENTS) {
-            if (name.equals(component.getName())) {
-                target = component;
-            }
-        }
-
-        if (target != null) {
-            COMPONENTS.remove(target);
-        }
-    }
-
-    /**
-     * Finds and returns the component with the specified name.
-     *
-     * @param name The name of the component that we're looking for
-     * @return The corresponding UpdateComponent, or null if it's not found
-     */
-    @Precondition("The specified name is not null")
-    public static UpdateComponent findComponent(final String name) {
-        assert name != null;
-
-        for (UpdateComponent component : COMPONENTS) {
-            if (name.equals(component.getName())) {
-                return component;
-            }
-        }
-
-        return null;
-    }
-
-    /**
-     * Removes the specified update from the list. This should be called when
-     * the update has finished, has encountered an error, or the user does not
-     * want the update to be performed.
-     *
-     * @param update The update to be removed
-     */
-    public static void removeUpdate(final Update update) {
-        update.removeUpdateListener(LISTENER);
-        UPDATES.remove(update);
-
-        if (UPDATES.isEmpty()) {
-            setStatus(STATE.IDLE);
-            updateCachedUpdates();
-        } else if (status == STATE.UPDATING) {
-            doNextUpdate();
-        }
-    }
-
-    /**
-     * Downloads and installs all known updates.
-     */
-    public static void applyUpdates() {
-        if (!UPDATES.isEmpty()) {
-            setStatus(STATE.UPDATING);
-            doNextUpdate();
-        }
-    }
-
-    /**
-     * Finds and applies the next pending update, or sets the state to idle
-     * / restart needed if appropriate.
-     */
-    private static void doNextUpdate() {
-        boolean restart = false;
-
-        for (Update update : UPDATES) {
-            if (update.getStatus() == UpdateStatus.PENDING) {
-                update.doUpdate();
-                return;
-            } else if (update.getStatus() == UpdateStatus.RESTART_NEEDED) {
-                restart = true;
-            }
-        }
-
-        setStatus(restart ? STATE.RESTART_REQUIRED : STATE.IDLE);
-        updateCachedUpdates();
-    }
-
-    /**
-     * Retrieves a list of components registered with the checker.
-     *
-     * @return A list of registered components
-     */
-    public static List<UpdateComponent> getComponents() {
-        return COMPONENTS;
-    }
-
-    /**
-     * Retrives a list of available updates from the checker.
-     *
-     * @return A list of available updates
-     */
-    public static List<Update> getAvailableUpdates() {
-        return UPDATES;
-    }
-
-
-    /**
-     * Adds a new status listener to the update checker.
-     *
-     * @param listener The listener to be added
-     */
-    public static void addListener(final UpdateCheckerListener listener) {
-        LISTENERS.add(UpdateCheckerListener.class, listener);
-    }
-
-    /**
-     * Removes a status listener from the update checker.
-     *
-     * @param listener The listener to be removed
-     */
-    public static void removeListener(final UpdateCheckerListener listener) {
-        LISTENERS.remove(UpdateCheckerListener.class, listener);
-    }
-
-    /**
-     * Retrieves the current status of the update checker.
-     *
-     * @return The update checker's current status
-     */
-    public static STATE getStatus() {
-        return status;
-    }
-
-    /**
-     * Sets the status of the update checker to the specified new status.
-     *
-     * @param newStatus The new status of this checker
-     */
-    private static void setStatus(final STATE newStatus) {
-        status = newStatus;
-
-        for (UpdateCheckerListener myListener : LISTENERS.get(UpdateCheckerListener.class)) {
-            myListener.statusChanged(newStatus);
-        }
-    }
-
-    /**
-     * Checks is a specified component is enabled.
-     *
-     * @param component Update component to check state
-     * @return true iif the update component is enabled
-     */
-    public static boolean isEnabled(final UpdateComponent component) {
-        return !IdentityManager.getIdentityManager().getGlobalConfiguration()
-                .hasOptionBool(DOMAIN, "enable-" + component.getName())
-                || IdentityManager.getIdentityManager().getGlobalConfiguration()
-                .getOptionBool(DOMAIN, "enable-" + component.getName());
-    }
-
 }

src/com/dmdirc/updater/checking/BaseCheckResult.java

@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.checking;
+
+import com.dmdirc.updater.UpdateComponent;
+import com.dmdirc.updater.Version;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.ToString;
+
+/**
+ * Simple implementation of {@link UpdateCheckResult}.
+ */
+@Getter
+@ToString
+@AllArgsConstructor
+@SuppressWarnings("PMD.UnusedPrivateField")
+public class BaseCheckResult implements UpdateCheckResult {
+
+    /** The component this result is for. */
+    private final UpdateComponent component;
+
+    /** Whether or not an update is available. */
+    private final boolean updateAvailable;
+
+    /** A user-friendly name of the updated version, if any. */
+    private final String updatedVersionName;
+
+    /** The version available to update to, if any. */
+    private final Version updatedVersion;
+
+    /**
+     * Creates a new {@link BaseCheckResult} which reports no update is
+     * available.
+     *
+     * @param component The component this result is for
+     */
+    public BaseCheckResult(final UpdateComponent component) {
+        this.component = component;
+        this.updateAvailable = false;
+        this.updatedVersion = null;
+        this.updatedVersionName = null;
+    }
+
+}

src/com/dmdirc/updater/checking/BaseDownloadableResult.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.checking;
+
+import com.dmdirc.updater.UpdateComponent;
+import com.dmdirc.updater.Version;
+
+import java.net.URL;
+
+import lombok.Getter;
+import lombok.ToString;
+
+/**
+ * A simple implementation of a {@link DownloadableUpdate}.
+ */
+@ToString(callSuper=true)
+@SuppressWarnings("PMD.UnusedPrivateField")
+public class BaseDownloadableResult extends BaseCheckResult implements DownloadableUpdate {
+
+    /** The URL the update may be downloaded from. */
+    @Getter
+    private final URL url;
+
+    /**
+     * Creates a new instance of {@link BaseDownloadableResult}.
+     *
+     * @param component The component that this result is for
+     * @param url The URL the update may be downloaded from
+     * @param updatedVersionName The friendly name of the updated version
+     * @param updatedVersion The version of the file available at that URL
+     */
+    public BaseDownloadableResult(final UpdateComponent component, final URL url,
+            final String updatedVersionName, final Version updatedVersion) {
+        super(component, true, updatedVersionName, updatedVersion);
+
+        this.url = url;
+    }
+
+}

src/com/dmdirc/updater/checking/CheckResultConsolidator.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.checking;
+
+import com.dmdirc.updater.UpdateComponent;
+
+import java.util.Collection;
+import java.util.Map;
+
+/**
+ *A {@link CheckResultConsolidator} defines a strategy for consolidating
+ * multiple sets of {@link UpdateCheckResult}s provided by different
+ * {@link UpdateCheckStrategy}s.
+ */
+public interface CheckResultConsolidator {
+
+    /**
+     * Consolidates the collection of results into a single mapping. The
+     * resulting map should contain one entry for each distinct component
+     * contained in any of the providing result sets, mapped to the best
+     * {@link UpdateCheckResult} according to this strategy.
+     *
+     * @param results The results to be consolidated
+     * @return A map of {@link UpdateComponent}s to their consolidated result
+     */
+    Map<UpdateComponent, UpdateCheckResult> consolidate(
+            Collection<Map<UpdateComponent, UpdateCheckResult>> results);
+}

src/com/dmdirc/updater/checking/DMDircCheckStrategy.java

@@ -0,0 +1,193 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.checking;
+
+import com.dmdirc.updater.UpdateChannel;
+import com.dmdirc.updater.UpdateComponent;
+import com.dmdirc.updater.Version;
+import com.dmdirc.util.io.Downloader;
+
+import java.io.IOException;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import lombok.AllArgsConstructor;
+import lombok.Setter;
+import lombok.extern.slf4j.Slf4j;
+
+/**
+ * A strategy which sends a request to the DMDirc update service for
+ * information.
+ */
+@Slf4j
+@AllArgsConstructor
+public class DMDircCheckStrategy implements UpdateCheckStrategy {
+
+    /** The URL to request to check for updates. */
+    private static final String UPDATE_URL = "http://updates.dmdirc.com/";
+
+    /** The update channel to check for updates on. */
+    @Setter
+    private UpdateChannel channel;
+
+    /** {@inheritDoc} */
+    @Override
+    public Map<UpdateComponent, UpdateCheckResult> checkForUpdates(final Collection<UpdateComponent> components) {
+        final Map<UpdateComponent, UpdateCheckResult> res
+                = new HashMap<UpdateComponent, UpdateCheckResult>();
+        final Map<String, UpdateComponent> names = getComponentsByName(components);
+
+        try {
+            final List<String> response = Downloader.getPage(UPDATE_URL, getPayload(components));
+            log.trace("Response from update server: {}", response);
+
+            for (String line : response) {
+                final UpdateComponent component = names.get(getComponent(line));
+
+                if (component == null) {
+                    log.warn("Unable to extract component from line: {}", line);
+                    continue;
+                }
+
+                final UpdateCheckResult result = parseResponse(component, line);
+
+                if (result != null) {
+                    res.put(component, result);
+                }
+            }
+        } catch (IOException ex) {
+            log.warn("I/O exception when checking for updates", ex);
+        }
+
+        return res;
+    }
+
+    /**
+     * Builds the data payload which will be sent to the update server.
+     * Specifically, iterates over each component and appends their name,
+     * the channel name, and the component's version number.
+     *
+     * @param components The components to be added to the payload
+     * @return A string which can be posted to the DMDirc update server
+     */
+    private String getPayload(final Collection<UpdateComponent> components) {
+        final StringBuilder data = new StringBuilder("data=");
+
+        for (UpdateComponent component : components) {
+            log.trace("Adding payload info for component {} (version {})",
+                    component.getName(), component.getVersion());
+
+            data.append(component.getName());
+            data.append(',');
+            data.append(channel.name());
+            data.append(',');
+            data.append(component.getVersion());
+            data.append(';');
+        }
+
+        log.debug("Constructed update payload: {}", data);
+
+        return data.toString();
+    }
+
+    /**
+     * Extracts the name of the component a given response line contains.
+     *
+     * @param line The line to be parsed
+     * @return The name of the component extracted from the given line
+     */
+    private String getComponent(final String line) {
+        final String[] parts = line.split(" ");
+
+        if ("outofdate".equals(parts[0])) {
+            return parts[1];
+        }
+
+        return parts[2];
+    }
+
+    /**
+     * Checks the specified line to determine the message from the update server.
+     *
+     * @param component The component the line refers to
+     * @param line The line to be checked
+     */
+    private UpdateCheckResult parseResponse(final UpdateComponent component,
+            final String line) {
+        final String[] parts = line.split(" ");
+
+        if ("outofdate".equals(parts[0])) {
+            return parseOutOfDateResponse(component, parts);
+        } else if ("uptodate".equals(parts[0])) {
+            return new BaseCheckResult(component);
+        } else if ("error".equals(parts[0])) {
+            log.warn("Error received from update server: {}", line);
+        } else {
+            log.error("Unknown update line received from server: {}", line);
+        }
+
+        return null;
+    }
+
+    /**
+     * Parses an "outofdate" response from the server. Extracts the URL,
+     * remote version and remote friendly version into a
+     * {@link BaseDownloadableResult}.
+     *
+     * @param parts The tokenised parts of the response line
+     * @return A corresponding {@link UpdateCheckResult} or null on failure
+     */
+    private UpdateCheckResult parseOutOfDateResponse(
+            final UpdateComponent component, final String[] parts) {
+        try {
+            return new BaseDownloadableResult(component, new URL(parts[5]),
+                    parts[4], new Version(parts[3]));
+        } catch (MalformedURLException ex) {
+            log.error("Unable to construct URL for update. Parts: {}", parts, ex);
+            return null;
+        }
+    }
+
+    /**
+     * Builds a mapping of components' names to their actual component
+     * objects.
+     *
+     * @param components A collection of components to be mapped
+     * @return A corresponding Map containing a single entry for each component,
+     * which the component's name as a key and the component itself as a value.
+     */
+    private Map<String, UpdateComponent> getComponentsByName(final Collection<UpdateComponent> components) {
+        final Map<String, UpdateComponent> res = new HashMap<String, UpdateComponent>();
+
+        for (UpdateComponent component : components) {
+            res.put(component.getName(), component);
+        }
+
+        return res;
+    }
+
+}

src/com/dmdirc/updater/OptionsComponent.java → src/com/dmdirc/updater/checking/DownloadableUpdate.java

@@ -20,18 +20,21 @@
  * SOFTWARE.
  */
 
-package com.dmdirc.updater;
+package com.dmdirc.updater.checking;
+
+import java.net.URL;
 
 /**
- * This interface is implemented by components that provide options for
- * upgrades.
+ * A specialised {@link UpdateCheckResult} that specifies where the update
+ * may be downloaded from.
  */
-public interface OptionsComponent {
+public interface DownloadableUpdate extends UpdateCheckResult {
 
     /**
-     * Retrieves the options for this component.
+     * Gets the URL that the update my be downloaded from.
      *
-     * @return Array containing the options for this component
+     * @return The update's download URL
      */
-    String[] getOptions();
+    URL getUrl();
+
 }

test/com/dmdirc/updater/UpdateTest.java → src/com/dmdirc/updater/checking/NaiveConsolidator.java

@@ -20,47 +20,36 @@
  * SOFTWARE.
  */
 
-package com.dmdirc.updater;
+package com.dmdirc.updater.checking;
 
-import com.dmdirc.config.IdentityManager;
-import com.dmdirc.updater.components.ClientComponent;
+import com.dmdirc.updater.UpdateComponent;
 
-import org.junit.Before;
-import org.junit.BeforeClass;
-import org.junit.Test;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
 
-import static org.junit.Assert.*;
-
-public class UpdateTest {
-
-    @BeforeClass
-    public static void setUpClass() throws Exception {
-        IdentityManager.getIdentityManager().initialise();
-    }
-
-    private static final String SUBJECT = "outofdate client channel date version url";
-
-    private Update update;
-
-    @Before
-    public void setUp() throws Exception {
-        UpdateChecker.init();
-        update = new Update(SUBJECT);
-    }
-
-    @Test
-    public void testGetComponent() {
-        assertTrue(update.getComponent() instanceof ClientComponent);
-    }
-
-    @Test
-    public void testGetRemoteVersion() {
-        assertEquals("version", update.getRemoteVersion());
-    }
-
-    @Test
-    public void testGetUrl() {
-        assertEquals("url", update.getUrl());
+/**
+ * A simple {@link CheckResultConsolidator} that returns the first check result
+ * for each component that has an update available.
+ */
+public class NaiveConsolidator implements CheckResultConsolidator {
+
+    /** {@inheritDoc} */
+    @Override
+    public Map<UpdateComponent, UpdateCheckResult> consolidate(
+            final Collection<Map<UpdateComponent, UpdateCheckResult>> results) {
+        final Map<UpdateComponent, UpdateCheckResult> res
+                = new HashMap<UpdateComponent, UpdateCheckResult>();
+
+        for (Map<UpdateComponent, UpdateCheckResult> set : results) {
+            for (Map.Entry<UpdateComponent, UpdateCheckResult> entry : set.entrySet()) {
+                if (!res.containsKey(entry.getKey()) || !res.get(entry.getKey()).isUpdateAvailable()) {
+                    res.put(entry.getKey(), entry.getValue());
+                }
+            }
+        }
+
+        return res;
     }
 
 }

src/com/dmdirc/updater/checking/UpdateCheckResult.java

@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.checking;
+
+import com.dmdirc.updater.UpdateComponent;
+import com.dmdirc.updater.Version;
+
+/**
+ * Defines the result of an update check. Specifically, provides whether or
+ * not the component in question is updatable, and to what version, and any
+ * additional information needed in order to effect an update.
+ */
+public interface UpdateCheckResult {
+
+    /**
+     * Retrieves the component that this result describes.
+     *
+     * @return The {@link UpdateComponent} that this result is for
+     */
+    UpdateComponent getComponent();
+
+    /**
+     * Indicates whether an update is available.
+     *
+     * @return True if an update was available, false otherwise
+     */
+    boolean isUpdateAvailable();
+
+    /**
+     * Returns the version that the component is updatable to. The behaviour
+     * of this method is not defined if {@link #isUpdateAvailable()} returns
+     * false.
+     *
+     * @return The version available for updating
+     */
+    Version getUpdatedVersion();
+
+    /**
+     * Returns a user-friendly version name of the version described by
+     * {@link #getUpdatedVersion()}. The behaviour of this method is not
+     * defined if {@link #isUpdateAvailable()} returns false.
+     *
+     * @return A user-friendly version name
+     */
+    String getUpdatedVersionName();
+
+}

src/com/dmdirc/updater/checking/UpdateCheckStrategy.java

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.checking;
+
+import com.dmdirc.updater.UpdateComponent;
+
+import java.util.Collection;
+import java.util.Map;
+
+/**
+ * Defines a strategy for checking for updates for one or more
+ * {@link UpdateComponent}s.
+ */
+public interface UpdateCheckStrategy {
+
+    /**
+     * Checks the given collection of components to determine whether or
+     * not any updates are available.
+     *
+     * @param components The components to be checked for updates
+     * @return A map of each of the provided component to an
+     * {@link UpdateCheckResult} indicating the status of the component and
+     * any additional information concerning how it should be updated.
+     */
+    Map<UpdateComponent, UpdateCheckResult> checkForUpdates(Collection<UpdateComponent> components);
+
+}

src/com/dmdirc/updater/components/ActionGroupComponent.java

@@ -47,8 +47,7 @@ public class ActionGroupComponent implements UpdateComponent {
         this.group = group;
 
         if (group.getComponent() != -1 && group.getVersion() != null) {
-            UpdateChecker.removeComponent(getName());
-            UpdateChecker.registerComponent(this);
+            UpdateChecker.getManager().addComponent(this);
         }
     }
 

src/com/dmdirc/updater/components/LauncherComponent.java

@@ -22,7 +22,6 @@
 
 package com.dmdirc.updater.components;
 
-import com.dmdirc.updater.OptionsComponent;
 import com.dmdirc.updater.UpdateChecker;
 import com.dmdirc.updater.UpdateComponent;
 import com.dmdirc.updater.Version;
@@ -30,12 +29,11 @@ import com.dmdirc.util.resourcemanager.ZipResourceManager;
 
 import java.io.File;
 import java.io.IOException;
-import java.util.Arrays;
 
 /**
  * Component for updates of DMDirc's launcher.
  */
-public class LauncherComponent implements UpdateComponent, OptionsComponent {
+public class LauncherComponent implements UpdateComponent {
 
     /** The platform of our current launcher. */
     private static String platform = "";
@@ -43,9 +41,6 @@ public class LauncherComponent implements UpdateComponent, OptionsComponent {
     /** The version of our current launcher. */
     private static Version version = new Version();
 
-    /** The options of our current launcher. */
-    private static String[] options = new String[]{};
-
     /**
      * Parses the specified launcher information.
      *
@@ -64,10 +59,9 @@ public class LauncherComponent implements UpdateComponent, OptionsComponent {
             version = new Version(info.substring(hpos + 1));
         } else {
             version = new Version(info.substring(hpos + 1, cpos));
-            options = info.substring(cpos + 1).split(",");
         }
 
-        UpdateChecker.registerComponent(new LauncherComponent());
+        UpdateChecker.getManager().addComponent(new LauncherComponent());
     }
 
     /**
@@ -103,13 +97,6 @@ public class LauncherComponent implements UpdateComponent, OptionsComponent {
         return version;
     }
 
-    /** {@inheritDoc} */
-    @Override
-    public String[] getOptions() {
-        return Arrays.copyOf(options, options.length);
-    }
-
-
     /** {@inheritDoc} */
     @Override
     public boolean requiresRestart() {

src/com/dmdirc/updater/components/PluginComponent.java

@@ -25,7 +25,6 @@ package com.dmdirc.updater.components;
 import com.dmdirc.config.ConfigManager;
 import com.dmdirc.config.IdentityManager;
 import com.dmdirc.plugins.PluginInfo;
-import com.dmdirc.updater.FileComponent;
 import com.dmdirc.updater.UpdateChecker;
 import com.dmdirc.updater.UpdateComponent;
 import com.dmdirc.updater.Version;
@@ -35,7 +34,7 @@ import java.io.File;
 /**
  * An update component for plugins.
  */
-public class PluginComponent implements UpdateComponent, FileComponent {
+public class PluginComponent implements UpdateComponent {
 
     /** The config to use. */
     private static final ConfigManager CONFIG = IdentityManager.getIdentityManager().getGlobalConfiguration();
@@ -54,8 +53,7 @@ public class PluginComponent implements UpdateComponent, FileComponent {
 
         if ((plugin.getMetaData().getUpdaterId() > 0 && plugin.getMetaData().getVersion().isValid())
                 || (CONFIG.hasOptionInt("plugin-addonid", plugin.getMetaData().getName()))) {
-            UpdateChecker.removeComponent(getName());
-            UpdateChecker.registerComponent(this);
+            UpdateChecker.getManager().addComponent(this);
         }
     }
 
@@ -138,9 +136,4 @@ public class PluginComponent implements UpdateComponent, FileComponent {
         return returnCode;
     }
 
-    @Override
-    public String getFileName() {
-        return plugin.getFilename();
-    }
-
 }

src/com/dmdirc/updater/installing/LegacyInstallationStrategy.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.installing;
+
+import com.dmdirc.updater.UpdateComponent;
+import com.dmdirc.updater.retrieving.SingleFileRetrievalResult;
+
+import lombok.ListenerSupport;
+import lombok.extern.slf4j.Slf4j;
+
+/**
+ * An {@link UpdateInstallationStrategy} which uses the old
+ * {@link UpdateComponent#doInstall(java.lang.String)} methods to perform
+ * installation.
+ */
+@Slf4j
+@ListenerSupport(UpdateInstallationListener.class)
+public class LegacyInstallationStrategy extends TypeSensitiveInstallationStrategy<UpdateComponent, SingleFileRetrievalResult> {
+
+    /**
+     * Creates a new {@link LegacyInstallationStrategy}.
+     */
+    public LegacyInstallationStrategy() {
+        super(UpdateComponent.class, SingleFileRetrievalResult.class);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    protected void installImpl(final UpdateComponent component, final SingleFileRetrievalResult retrievalResult) {
+        log.info("Installing file from {} for component {} using legacy strategy",
+                retrievalResult.getFile(), component.getName());
+
+        try {
+            component.doInstall(retrievalResult.getFile().getAbsolutePath());
+            fireInstallCompleted(component);
+        } catch (Exception ex) {
+            log.warn("Error installing update for {}", component.getName(), ex);
+            fireInstallFailed(component);
+        }
+    }
+
+}

src/com/dmdirc/updater/installing/TypeSensitiveInstallationStrategy.java

@@ -0,0 +1,49 @@
+
+package com.dmdirc.updater.installing;
+
+import com.dmdirc.updater.UpdateComponent;
+import com.dmdirc.updater.retrieving.UpdateRetrievalResult;
+
+import lombok.AllArgsConstructor;
+
+/**
+ * Base class for {@link UpdateInstallationStrategy} implementations that
+ * can only handle a specific sublcass of {@link UpdateComponent} or
+ * {@link UpdateRetrievalResult}.
+ *
+ * @param <S> The type of {@link UpdateComponent} that can be handled
+ * @param <T> The type of {@link UpdateRetrievalResult} that can be handled
+ */
+@AllArgsConstructor
+public abstract class TypeSensitiveInstallationStrategy<S extends UpdateComponent,T extends UpdateRetrievalResult>
+        implements UpdateInstallationStrategy {
+
+    /** The type of {@link UpdateComponent} that can be handled. */
+    private final Class<S> updateComponentClass;
+
+    /** The type of {@link UpdateRetrievalResult} that can be handled. */
+    private final Class<T> updateRetrievalClass;
+
+    /** {@inheritDoc} */
+    @Override
+    public boolean canHandle(final UpdateRetrievalResult retrievalResult) {
+        return updateComponentClass.isAssignableFrom(retrievalResult.getCheckResult().getComponent().getClass())
+                && updateRetrievalClass.isAssignableFrom(retrievalResult.getClass());
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    @SuppressWarnings("unchecked")
+    public void install(final UpdateRetrievalResult retrievalResult) {
+        installImpl((S) retrievalResult.getCheckResult().getComponent(), (T) retrievalResult);
+    }
+
+    /**
+     * Installs the retrieved update for the given component.
+     *
+     * @param component The component to be updated
+     * @param retrievalResult The result of the retrieval operation
+     */
+    protected abstract void installImpl(S component, T retrievalResult);
+
+}

src/com/dmdirc/updater/installing/UpdateInstallationListener.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.installing;
+
+import com.dmdirc.updater.UpdateComponent;
+
+/**
+ * Interface for objects interested in the progress of an installation attempt
+ * performed by an {@link UpdateInstallationStrategy}.
+ */
+public interface UpdateInstallationListener {
+
+    /**
+     * Called when the progress of an install has changed.
+     *
+     * @param component The component being installed
+     * @param progress The percentage progress completed (0-100)
+     */
+    void installProgressChanged(UpdateComponent component, double progress);
+
+    /**
+     * Called when an installation has failed.
+     *
+     * @param component The component that failed to install
+     */
+    void installFailed(UpdateComponent component);
+
+    /**
+     * Called when an installation has finished.
+     *
+     * @param component The component that was successfully installed
+     */
+    void installCompleted(UpdateComponent component);
+
+}

src/com/dmdirc/updater/installing/UpdateInstallationStrategy.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.installing;
+
+import com.dmdirc.updater.retrieving.UpdateRetrievalResult;
+import com.dmdirc.updater.retrieving.UpdateRetrievalStategy;
+
+/**
+ * Describes a strategy for installing updates which have been retrieved
+ * by a {@link UpdateRetrievalStategy}.
+ */
+public interface UpdateInstallationStrategy {
+
+    /**
+     * Determines whether this strategy can handle the installation of
+     * the given retrieved update for the given component.
+     *
+     * @param retrievalResult The result of the retrieval operation
+     * @return True if this strategy can perform installation; false otherwise
+     */
+    boolean canHandle(UpdateRetrievalResult retrievalResult);
+
+    /**
+     * Installs the retrieved update for the given component.
+     *
+     * @param retrievalResult The result of the retrieval operation
+     */
+    void install(UpdateRetrievalResult retrievalResult);
+
+    /**
+     * Adds a new status listener to this strategy.
+     *
+     * @param listener The listener to be registered
+     */
+    void addUpdateInstallationListener(UpdateInstallationListener listener);
+
+    /**
+     * Removes the given listener from this strategy.
+     *
+     * @param listener The listener to be removed
+     */
+    void removeUpdateInstallationListener(UpdateInstallationListener listener);
+
+}

src/com/dmdirc/updater/manager/CachingUpdateManager.java

@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.manager;
+
+import com.dmdirc.updater.UpdateComponent;
+
+/**
+ * A specialised {@link UpdateManager} which caches the update status of each
+ * {@link UpdateComponent}.
+ */
+public interface CachingUpdateManager extends UpdateManager {
+
+    /**
+     * Gets the current status of the given component.
+     *
+     * @param component The component to get a status for
+     * @return The current status of the component
+     */
+    UpdateStatus getStatus(UpdateComponent component);
+
+    /**
+     * Gets the overall status of the manager.
+     *
+     * @return The current status of the manager
+     */
+    UpdateManagerStatus getManagerStatus();
+
+    /**
+     * Adds a new {@link UpdateManagerListener} to this manager, which will
+     * be informed when the manager's status changes.
+     *
+     * @param listener The listener to be added
+     */
+    void addUpdateManagerListener(UpdateManagerListener listener);
+
+    /**
+     * Removes the specified listener from this manager.
+     *
+     * @param listener The listener to be removed
+     */
+    void removeUpdateManagerListener(UpdateManagerListener listener);
+
+}

src/com/dmdirc/updater/manager/CachingUpdateManagerImpl.java

@@ -0,0 +1,142 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.manager;
+
+import com.dmdirc.updater.UpdateComponent;
+import com.dmdirc.updater.checking.CheckResultConsolidator;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.Executor;
+
+import lombok.Getter;
+import lombok.ListenerSupport;
+
+/**
+ * An extension of {@link UpdateManagerImpl} which implements status caching
+ * functionality.
+ */
+@ListenerSupport(UpdateManagerListener.class)
+public class CachingUpdateManagerImpl extends UpdateManagerImpl implements CachingUpdateManager {
+
+    /** Map of component to their most recent status. */
+    private final Map<UpdateComponent, UpdateStatus> cachedStatuses
+            = new HashMap<UpdateComponent, UpdateStatus>();
+
+    /** Our current status. */
+    @Getter
+    private UpdateManagerStatus managerStatus = UpdateManagerStatus.IDLE;
+
+    /**
+     * Creates a new instance of {@link CachingUpdateManagerImpl}.
+     *
+     * @param executor The executor to use to schedule tasks
+     * @param consolidator The consolidator to use to merge check results
+     * @param policy The policy to apply to update components
+     */
+    public CachingUpdateManagerImpl(final Executor executor,
+            final CheckResultConsolidator consolidator,
+            final UpdateComponentPolicy policy) {
+        super(executor, consolidator, policy);
+
+        addUpdateStatusListener(new Listener());
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public UpdateStatus getStatus(final UpdateComponent component) {
+        return cachedStatuses.get(component);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public void addComponent(final UpdateComponent component) {
+        super.addComponent(component);
+        cachedStatuses.put(component, getPolicy().canCheck(component)
+                ? UpdateStatus.IDLE : UpdateStatus.CHECKING_NOT_PERMITTED);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public void removeComponent(final UpdateComponent component) {
+        super.removeComponent(component);
+        cachedStatuses.remove(component);
+    }
+
+    /**
+     * Determines the current status of this manager, using the
+     * cached status of each update component. If the status has changed,
+     * fires the {@link UpdateManagerListener#updateManagerStatusChanged(com.dmdirc.updater.manager.UpdateManager, com.dmdirc.updater.manager.UpdateManagerStatus)}
+     * method on registered listeners.
+     */
+    private void checkStatus() {
+        UpdateManagerStatus newStatus = UpdateManagerStatus.IDLE;
+        UpdateManagerStatus componentStatus;
+
+        for (UpdateStatus cachedStatus : cachedStatuses.values()) {
+            switch (cachedStatus) {
+                case CHECKING:
+                case INSTALLING:
+                case RETRIEVING:
+                    componentStatus = UpdateManagerStatus.WORKING;
+                    break;
+                case UPDATE_PENDING:
+                case INSTALL_PENDING:
+                    componentStatus = UpdateManagerStatus.IDLE_UPDATE_AVAILABLE;
+                    break;
+                case RESTART_PENDING:
+                    componentStatus = UpdateManagerStatus.IDLE_RESTART_NEEDED;
+                    break;
+                case UPDATED:
+                case IDLE:
+                default:
+                    componentStatus = UpdateManagerStatus.IDLE;
+            }
+
+            if (componentStatus.compareTo(newStatus) < 0) {
+                newStatus = componentStatus;
+            }
+        }
+
+        if (managerStatus != newStatus) {
+            managerStatus = newStatus;
+            fireUpdateManagerStatusChanged(this, managerStatus);
+        }
+    }
+
+    /**
+     * Status listener which updates the {@link #cachedStatuses} map.
+     */
+    private class Listener implements UpdateStatusListener {
+
+        /** {@inheritDoc} */
+        @Override
+        public void updateStatusChanged(final UpdateComponent component,
+                final UpdateStatus status, final double progress) {
+            cachedStatuses.put(component, status);
+            checkStatus();
+        }
+
+    }
+
+}

src/com/dmdirc/updater/manager/ConfigComponentPolicy.java

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.manager;
+
+import com.dmdirc.config.ConfigManager;
+import com.dmdirc.updater.UpdateComponent;
+
+import lombok.RequiredArgsConstructor;
+
+/**
+ * An {@link UpdateComponentPolicy} which checks if the component is enabled
+ * in DMDirc's configuration.
+ */
+@RequiredArgsConstructor
+public class ConfigComponentPolicy implements UpdateComponentPolicy {
+
+    /** The configuration manager to check. */
+    private final ConfigManager manager;
+
+    /** {@inheritDoc} */
+    @Override
+    public boolean canCheck(final UpdateComponent component) {
+        return !manager.hasOptionBool("updater", "enable-" + component.getName())
+                || manager.getOptionBool("updater", "enable-" + component.getName());
+    }
+
+}

src/com/dmdirc/updater/manager/DMDircUpdateManager.java

@@ -0,0 +1,108 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.manager;
+
+import com.dmdirc.config.ConfigBinding;
+import com.dmdirc.config.ConfigManager;
+import com.dmdirc.updater.UpdateChannel;
+import com.dmdirc.updater.checking.DMDircCheckStrategy;
+import com.dmdirc.updater.checking.NaiveConsolidator;
+import com.dmdirc.updater.components.ClientComponent;
+import com.dmdirc.updater.components.DefaultsComponent;
+import com.dmdirc.updater.components.ModeAliasesComponent;
+import com.dmdirc.updater.installing.LegacyInstallationStrategy;
+import com.dmdirc.updater.retrieving.DownloadRetrievalStrategy;
+
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+
+import lombok.extern.slf4j.Slf4j;
+
+/**
+ * Specialised update manager for DMDirc.
+ */
+@Slf4j
+public class DMDircUpdateManager extends CachingUpdateManagerImpl {
+
+    /** The default check strategy we use. */
+    private final DMDircCheckStrategy checkStrategy;
+
+    /**
+     * Creates a new instance of the update manager.
+     *
+     * @param configManager The config manager to use to retrieve channel info
+     * @param tempFolder Temporary folder to use for downloading updates
+     * @param threads The number of threads to use for updating
+     */
+    public DMDircUpdateManager(final ConfigManager configManager,
+            final String tempFolder, final int threads) {
+        super(new ThreadPoolExecutor(threads, threads, 1, TimeUnit.MINUTES,
+                new LinkedBlockingQueue<Runnable>(), new NamedThreadFactory()),
+                new NaiveConsolidator(),
+                new ConfigComponentPolicy(configManager));
+
+        addComponent(new ClientComponent());
+        addComponent(new ModeAliasesComponent());
+        addComponent(new DefaultsComponent());
+
+        checkStrategy = new DMDircCheckStrategy(UpdateChannel.STABLE);
+
+        configManager.getBinder().bind(this, DMDircUpdateManager.class);
+
+        addCheckStrategy(checkStrategy);
+        addRetrievalStrategy(new DownloadRetrievalStrategy(tempFolder));
+        addInstallationStrategy(new LegacyInstallationStrategy());
+    }
+
+    /**
+     * Sets the channel which will be used by the {@link DMDircCheckStrategy}.
+     *
+     * @param channel The new channel to use
+     */
+    @ConfigBinding(domain="updater", key="channel")
+    public void setChannel(final String channel) {
+        log.info("Changing channel to {}", channel);
+
+        try {
+            checkStrategy.setChannel(UpdateChannel.valueOf(channel.toUpperCase()));
+        } catch (IllegalArgumentException ex) {
+            log.warn("Unknown channel {}", channel, ex);
+        }
+    }
+
+    /**
+     * Thread factory which returns named threads.
+     */
+    private static class NamedThreadFactory implements ThreadFactory {
+
+        /** {@inheritDoc} */
+        @Override
+        public Thread newThread(final Runnable r) {
+            return new Thread(r, "Updater thread");
+        }
+
+    }
+
+}

src/com/dmdirc/updater/manager/InstallationTask.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.manager;
+
+import com.dmdirc.updater.installing.UpdateInstallationStrategy;
+import com.dmdirc.updater.retrieving.UpdateRetrievalResult;
+
+import lombok.RequiredArgsConstructor;
+
+/**
+ * Task which installs an update using a given
+ * {@link UpdateInstallationStrategy}.
+ */
+@RequiredArgsConstructor
+public class InstallationTask implements Runnable {
+
+    /** The strategy to use to install the update. */
+    private final UpdateInstallationStrategy strategy;
+
+    /** The update which will be installed. */
+    private final UpdateRetrievalResult result;
+
+    /** {@inheritDoc} */
+    @Override
+    public void run() {
+        strategy.install(result);
+    }
+
+}

src/com/dmdirc/updater/manager/RetrievalTask.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.manager;
+
+import com.dmdirc.updater.checking.UpdateCheckResult;
+import com.dmdirc.updater.retrieving.UpdateRetrievalResult;
+import com.dmdirc.updater.retrieving.UpdateRetrievalStategy;
+
+import lombok.RequiredArgsConstructor;
+
+/**
+ * Task which retrieves an available update using the given
+ * {@link UpdateRetrievalStategy} and passes the result back to the
+ * {@link UpdateManagerImpl}.
+ */
+@RequiredArgsConstructor
+public class RetrievalTask implements Runnable {
+
+    /** The update manager launching this task. */
+    private final UpdateManagerImpl manager;
+
+    /** The strategy to use to retrieve the update. */
+    private final UpdateRetrievalStategy strategy;
+
+    /** The update which will be downloaded. */
+    private final UpdateCheckResult result;
+
+    /** Whether to install afterwards or not. */
+    private final boolean install;
+
+    /** {@inheritDoc} */
+    @Override
+    public void run() {
+        final UpdateRetrievalResult retrievalResult = strategy.retrieve(result);
+
+        if (retrievalResult.isSuccessful()) {
+            manager.setRetrievalResult(retrievalResult);
+
+            if (install) {
+                manager.install(retrievalResult.getCheckResult().getComponent());
+            }
+        }
+    }
+
+}

src/com/dmdirc/updater/manager/UpdateComponentPolicy.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.manager;
+
+import com.dmdirc.updater.UpdateComponent;
+
+/**
+ * Defines a policy to determine whether certain {@link UpdateComponent}s can
+ * be updated.
+ */
+public interface UpdateComponentPolicy {
+
+    /**
+     * Determines whether the manager can check for updates for the given
+     * component.
+     *
+     * @param component The component in question
+     * @return True if the manager is allowed to check this component, false
+     * otherwise
+     */
+    boolean canCheck(UpdateComponent component);
+
+}

src/com/dmdirc/updater/manager/UpdateManager.java

@@ -0,0 +1,142 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.manager;
+
+import com.dmdirc.updater.UpdateComponent;
+import com.dmdirc.updater.checking.UpdateCheckResult;
+import com.dmdirc.updater.checking.UpdateCheckStrategy;
+import com.dmdirc.updater.installing.UpdateInstallationStrategy;
+import com.dmdirc.updater.retrieving.UpdateRetrievalStategy;
+
+import java.util.Collection;
+
+/**
+ * Manages the update process for a collection of {@link UpdateComponent}s.
+ */
+public interface UpdateManager {
+
+    /**
+     * Adds a new check strategy to this manager. {@link UpdateCheckStrategy}s
+     * are responsible for checking to see if an updated version of a set of
+     * components is available. If multiple strategies are configured, their
+     * results are merged using this manager's {@link CheckResultConsolidator}.
+     *
+     * @param strategy The strategy to be added.
+     */
+    void addCheckStrategy(final UpdateCheckStrategy strategy);
+
+    /**
+     * Adds a new installation strategy to this manager.
+     * {@link UpdateInstallationStrategy}s are responsible for handling the
+     * installation of an update once it has been retrieved.
+     *
+     * @param strategy The strategy to be added.
+     */
+    void addInstallationStrategy(final UpdateInstallationStrategy strategy);
+
+    /**
+     * Adds a new retrieval strategy to this manager.
+     * {@link UpdateRetrievalStategy}s are responsible for retrieving the
+     * updated version of a component after an update has been identified
+     * by a {@link UpdateCheckStrategy}.
+     *
+     * @param strategy The strategy to be added.
+     */
+    void addRetrievalStrategy(final UpdateRetrievalStategy strategy);
+
+    /**
+     * Adds a new component to this manager. Components will be checked for
+     * updates the next time {@link #checkForUpdates()} is called. If a
+     * component with the same name already exists, it will be removed.
+     *
+     * @param component The component to be added
+     */
+    void addComponent(final UpdateComponent component);
+
+    /**
+     * Removes the specified component from this manager. If any operations
+     * are pending for the component they may complete after this method has
+     * been called.
+     *
+     * @param component The component to be removed
+     */
+    void removeComponent(final UpdateComponent component);
+
+    /**
+     * Retrieves the collection of all components known by this manager.
+     *
+     * @return The set of all known {@link UpdateComponent}s.
+     */
+    Collection<UpdateComponent> getComponents();
+
+    /**
+     * Checks for updates for all registered {@link UpdateComponent}s.
+     */
+    void checkForUpdates();
+
+    /**
+     * Installs any updates for the specified component. If an update for the
+     * component is available but has not yet been retrieved, this method
+     * should perform in the same way to a synchronous call to
+     * {@link #retrieve(com.dmdirc.updater.UpdateComponent)} followed by
+     * {@link #install(com.dmdirc.updater.UpdateComponent)}.
+     *
+     * @param component The component to be installed
+     */
+    void install(UpdateComponent component);
+
+    /**
+     * Retrieves any update associated with the given component. The update
+     * will not be installed until the
+     * {@link #install(com.dmdirc.updater.UpdateComponent)} method is called.
+     *
+     * @param component The component to retrieve updates for
+     */
+    void retrieve(UpdateComponent component);
+
+    /**
+     * Retrieves the last update check result for the given component.
+     *
+     * @param component The component to retrieve a check result for
+     * @return The component's most recent associated {@link UpdateCheckResult},
+     * or <code>null</code> if the component has not been checked or has since
+     * been updated.
+     */
+    UpdateCheckResult getCheckResult(UpdateComponent component);
+
+    /**
+     * Adds the given status listener to this manager. The listener will be
+     * called for any future status changes caused by this manager.
+     *
+     * @param listener The listener to be added
+     */
+    void addUpdateStatusListener(UpdateStatusListener listener);
+
+    /**
+     * Removes the given status listener from this manager.
+     *
+     * @param listener The listener to be removed
+     */
+    void removeUpdateStatusListener(UpdateStatusListener listener);
+
+}

src/com/dmdirc/updater/manager/UpdateManagerImpl.java

@@ -0,0 +1,358 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.manager;
+
+import com.dmdirc.updater.UpdateComponent;
+import com.dmdirc.updater.checking.CheckResultConsolidator;
+import com.dmdirc.updater.checking.UpdateCheckResult;
+import com.dmdirc.updater.checking.UpdateCheckStrategy;
+import com.dmdirc.updater.installing.UpdateInstallationListener;
+import com.dmdirc.updater.installing.UpdateInstallationStrategy;
+import com.dmdirc.updater.retrieving.UpdateRetrievalListener;
+import com.dmdirc.updater.retrieving.UpdateRetrievalResult;
+import com.dmdirc.updater.retrieving.UpdateRetrievalStategy;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.concurrent.Executor;
+
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.ListenerSupport;
+import lombok.extern.slf4j.Slf4j;
+
+/**
+ * Concrete implementation of {@link UpdateManager}.
+ */
+@Slf4j
+@AllArgsConstructor
+@ListenerSupport(UpdateStatusListener.class)
+public class UpdateManagerImpl implements UpdateManager {
+
+    /** Collection of known update checking strategies. */
+    private final List<UpdateCheckStrategy> checkers
+            = new CopyOnWriteArrayList<UpdateCheckStrategy>();
+
+    /** Collection of known update retrieval strategies. */
+    private final List<UpdateRetrievalStategy> retrievers
+            = new CopyOnWriteArrayList<UpdateRetrievalStategy>();
+
+    /** Collection of known update installation strategies. */
+    private final List<UpdateInstallationStrategy> installers
+            = new CopyOnWriteArrayList<UpdateInstallationStrategy>();
+
+    /** Map of known component names to their components. */
+    private final Map<String, UpdateComponent> components
+            = new HashMap<String, UpdateComponent>();
+
+    /** Listener used to proxy retrieval events. */
+    private final UpdateRetrievalListener retrievalListener
+            = new RetrievalListener();
+
+    /** Listener used to proxy setRetrievalResult events. */
+    private final UpdateInstallationListener installationListener
+            = new InstallListener();
+
+    /** Cache of update check results. */
+    private final Map<UpdateComponent, UpdateCheckResult> checkResults
+            = new HashMap<UpdateComponent, UpdateCheckResult>();
+
+    /** Cache of retrieval results. */
+    private final Map<UpdateComponent, UpdateRetrievalResult> retrievalResults
+            = new HashMap<UpdateComponent, UpdateRetrievalResult>();
+
+    /** Executor to use to schedule retrieval and installation jobs. */
+    private final Executor executor;
+
+    /** Consolidator to use to merge multiple check results. */
+    @Getter(AccessLevel.PROTECTED)
+    private final CheckResultConsolidator consolidator;
+
+    /** The policy to use to determine whether updates are enabled. */
+    @Getter(AccessLevel.PROTECTED)
+    private final UpdateComponentPolicy policy;
+
+    /** {@inheritDoc} */
+    @Override
+    public void addCheckStrategy(final UpdateCheckStrategy strategy) {
+        log.trace("Adding new check strategy: {}", strategy);
+        this.checkers.add(strategy);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public void addRetrievalStrategy(final UpdateRetrievalStategy strategy) {
+        log.trace("Adding new retrieval strategy: {}", strategy);
+        strategy.addUpdateRetrievalListener(retrievalListener);
+        this.retrievers.add(strategy);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public void addInstallationStrategy(final UpdateInstallationStrategy strategy) {
+        log.trace("Adding new installation strategy: {}", strategy);
+        strategy.addUpdateInstallationListener(installationListener);
+        this.installers.add(strategy);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public void addComponent(final UpdateComponent component) {
+        log.trace("Adding new component: {}", component);
+        this.components.put(component.getName(), component);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public void removeComponent(final UpdateComponent component) {
+        log.trace("Removing component: {}", component);
+        this.components.remove(component.getName());
+        this.checkResults.remove(component);
+        this.retrievalResults.remove(component);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public Collection<UpdateComponent> getComponents() {
+        return Collections.unmodifiableCollection(this.components.values());
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public UpdateCheckResult getCheckResult(final UpdateComponent component) {
+        return checkResults.get(component);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public void checkForUpdates() {
+        final Collection<Map<UpdateComponent, UpdateCheckResult>> results
+                = new ArrayList<Map<UpdateComponent, UpdateCheckResult>>();
+
+        log.info("Checking for updates for {} components using {} strategies",
+                components.size(), checkers.size());
+        log.trace("Components: {}", components);
+        log.trace("Strategies: {}", checkers);
+
+        final List<UpdateComponent> enabledComponents
+                = new ArrayList<UpdateComponent>(components.size());
+
+        for (UpdateComponent component : components.values()) {
+            if (policy.canCheck(component)) {
+                fireUpdateStatusChanged(component, UpdateStatus.CHECKING, 0);
+                enabledComponents.add(component);
+            } else {
+                log.debug("Checking for updates for {} denied by policy", component.getName());
+                fireUpdateStatusChanged(component, UpdateStatus.CHECKING_NOT_PERMITTED, 0);
+            }
+        }
+
+        for (UpdateCheckStrategy strategy : checkers) {
+            results.add(strategy.checkForUpdates(enabledComponents));
+        }
+
+        checkResults.putAll(consolidator.consolidate(results));
+
+        for (UpdateComponent component : enabledComponents) {
+            if (checkResults.containsKey(component) && checkResults.get(component).isUpdateAvailable()) {
+                log.trace("Update is available for {}", component);
+                fireUpdateStatusChanged(component, UpdateStatus.UPDATE_PENDING, 0);
+            } else {
+                fireUpdateStatusChanged(component, UpdateStatus.IDLE, 0);
+            }
+        }
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public void install(final UpdateComponent component) {
+        if (!retrievalResults.containsKey(component) || !retrievalResults.get(component).isSuccessful()) {
+            // Not downloaded yet - try retrieving first
+            retrieve(component, true);
+            return;
+        }
+
+        final UpdateRetrievalResult update = retrievalResults.get(component);
+        final UpdateInstallationStrategy strategy = getStrategy(update);
+
+        if (strategy == null) {
+            fireUpdateStatusChanged(component, UpdateStatus.IDLE, 0);
+        } else {
+            fireUpdateStatusChanged(component, UpdateStatus.INSTALL_PENDING, 0);
+            log.debug("Scheduling install for {}", update);
+            executor.execute(new InstallationTask(strategy, update));
+        }
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public void retrieve(final UpdateComponent component) {
+        retrieve(component, false);
+    }
+
+    /**
+     * Retrieves updates for the given component, optionally installing if
+     * retrieval is successful.
+     *
+     * @param component The component to be retrieved
+     * @param install True to install automatically, false to just retrieve
+     */
+    public void retrieve(final UpdateComponent component, final boolean install) {
+        if (!checkResults.containsKey(component) || !checkResults.get(component).isUpdateAvailable()) {
+            log.warn("Tried to retrieve component with no update: {}", component);
+            return;
+        }
+
+        final UpdateCheckResult update = checkResults.get(component);
+        final UpdateRetrievalStategy strategy = getStrategy(update);
+
+        if (strategy == null) {
+            fireUpdateStatusChanged(component, UpdateStatus.IDLE, 0);
+        } else {
+            fireUpdateStatusChanged(component, UpdateStatus.UPDATE_PENDING, 0);
+            log.debug("Scheduling retrieval for {}", update);
+            executor.execute(new RetrievalTask(this, strategy, update, install));
+        }
+    }
+
+    /**
+     * Sets the retrieval result for an {@link UpdateComponent}.
+     *
+     * @param result The result retrieved from the {@link UpdateRetrievalStategy}.
+     */
+    protected void setRetrievalResult(final UpdateRetrievalResult result) {
+        log.debug("Received retrieval result {}", result);
+        retrievalResults.put(result.getCheckResult().getComponent(), result);
+
+        if (result.isSuccessful()) {
+            checkResults.remove(result.getCheckResult().getComponent());
+        }
+    }
+
+    /**
+     * Gets an appropriate retrieval strategy for the given check result.
+     * Iterates over the set of known strategies and returns the first which
+     * claims to be able to handle the result.
+     *
+     * @param result The result to find a strategy for
+     * @return A relevant strategy, or <code>null</code> if none are available
+     */
+    protected UpdateRetrievalStategy getStrategy(final UpdateCheckResult result) {
+        log.debug("Trying to find retrieval strategy for {}", result);
+
+        for (UpdateRetrievalStategy strategy : retrievers) {
+            log.trace("Testing strategy {}", strategy);
+
+            if (strategy.canHandle(result)) {
+                log.debug("Found strategy {}", strategy);
+                return strategy;
+            }
+        }
+
+        log.warn("No strategy found to retrieve {}", result);
+        return null;
+    }
+
+    /**
+     * Gets an appropriate installation strategy for the given retrieval result.
+     * Iterates over the set of known strategies and returns the first which
+     * claims to be able to handle the result.
+     *
+     * @param result The result to find a strategy for
+     * @return A relevant strategy, or <code>null</code> if none are available
+     */
+    protected UpdateInstallationStrategy getStrategy(final UpdateRetrievalResult result) {
+        log.debug("Trying to find installation strategy for {}", result);
+
+        for (UpdateInstallationStrategy strategy : installers) {
+            log.trace("Testing strategy {}", strategy);
+
+            if (strategy.canHandle(result)) {
+                log.debug("Found strategy {}", strategy);
+                return strategy;
+            }
+        }
+
+        log.warn("No strategy found to install {}", result);
+        return null;
+    }
+
+    /**
+     * Listens for changes announced by {@link UpdateInstallationStrategy}s
+     * and proxies them on to the manager's own {@link UpdateStatusListener}s.
+     */
+    private class InstallListener implements UpdateInstallationListener {
+
+        /** {@inheritDoc} */
+        @Override
+        public void installCompleted(final UpdateComponent component) {
+            fireUpdateStatusChanged(component, component.requiresRestart()
+                    ? UpdateStatus.RESTART_PENDING : UpdateStatus.UPDATED, 0);
+        }
+
+        /** {@inheritDoc} */
+        @Override
+        public void installFailed(final UpdateComponent component) {
+            fireUpdateStatusChanged(component, UpdateStatus.IDLE, 0);
+        }
+
+        /** {@inheritDoc} */
+        @Override
+        public void installProgressChanged(final UpdateComponent component, final double progress) {
+            fireUpdateStatusChanged(component, UpdateStatus.INSTALLING, progress);
+        }
+
+    }
+
+    /**
+     * Listens for changes announced by {@link UpdateRetrievalStrategy}s
+     * and proxies them on to the manager's own {@link UpdateStatusListener}s.
+     */
+    private class RetrievalListener implements UpdateRetrievalListener {
+
+        /** {@inheritDoc} */
+        @Override
+        public void retrievalCompleted(final UpdateComponent component) {
+            fireUpdateStatusChanged(component, UpdateStatus.INSTALL_PENDING, 0);
+        }
+
+        /** {@inheritDoc} */
+        @Override
+        public void retrievalFailed(final UpdateComponent component) {
+            fireUpdateStatusChanged(component, UpdateStatus.IDLE, 0);
+        }
+
+        /** {@inheritDoc} */
+        @Override
+        public void retrievalProgressChanged(final UpdateComponent component, final double progress) {
+            fireUpdateStatusChanged(component, UpdateStatus.RETRIEVING, progress);
+        }
+
+    }
+}

src/com/dmdirc/updater/FileComponent.java → src/com/dmdirc/updater/manager/UpdateManagerListener.java

@@ -20,18 +20,20 @@
  * SOFTWARE.
  */
 
-package com.dmdirc.updater;
+package com.dmdirc.updater.manager;
 
 /**
- * This interface is implemented by components that are related to a specific
- * file.
+ * Interface for objects interested in the status of a
+ * {@link CachingUpdateManager}.
  */
-public interface FileComponent {
+public interface UpdateManagerListener {
 
     /**
-     * Retrieves the file name of this component.
+     * Called when the status of the {@link UpdateManager} changes.
      *
-     * @return This component's file name
+     * @param manager The manager whose status has changed
+     * @param status The new status of the manager
      */
-    String getFileName();
+    void updateManagerStatusChanged(UpdateManager manager, UpdateManagerStatus status);
+
 }

src/com/dmdirc/updater/manager/UpdateManagerStatus.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.manager;
+
+/**
+ * Enumerates the possible states of a {@link CachingUpdateManager}. The
+ * statuses are ordered according to priority, with the first being the
+ * highest priority.
+ */
+public enum UpdateManagerStatus {
+
+    /** The manager is currently performing some task. */
+    WORKING,
+
+    /** The manager is {@link #IDLE} but there are updates available. */
+    IDLE_UPDATE_AVAILABLE,
+
+    /** The manager is {@link #IDLE} but a restart is needed. */
+    IDLE_RESTART_NEEDED,
+
+    /** The manager is idle and not performing any activity. */
+    IDLE,
+
+}

src/com/dmdirc/updater/manager/UpdateStatus.java

@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.manager;
+
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+/**
+ * Describes the possible statuses of an {@link UpdateComponent}.
+ */
+@RequiredArgsConstructor
+@SuppressWarnings("PMD.UnusedPrivateField")
+public enum UpdateStatus {
+
+    /** There is no known update available, and the manager is not active checking. */
+    IDLE("Idle"),
+
+    /** The update manager is not permitted to check for updates for this component. */
+    CHECKING_NOT_PERMITTED("Not enabled"),
+
+    /** The manager is currently checking for updates for the component. */
+    CHECKING("Checking..."),
+
+    /** An update is available but it is not currently being retrieved. */
+    UPDATE_PENDING("Update available"),
+
+    /** An update is currently being retrieved. */
+    RETRIEVING("Retrieving..."),
+
+    /** An update has been retrieved but it is not currently being installed. */
+    INSTALL_PENDING("Retrieved"),
+
+    /** An update is currently being installed. */
+    INSTALLING("Installing..."),
+
+    /** An update has successfully been installed. */
+    UPDATED("Updated"),
+
+    /** An update has been installed but will not take effect until after a restart. */
+    RESTART_PENDING("Restart required");
+
+    /** Textual description of the status. */
+    @Getter
+    private final String description;
+
+}

src/com/dmdirc/updater/manager/UpdateStatusListener.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.manager;
+
+import com.dmdirc.updater.UpdateComponent;
+
+/**
+ * Interface for objects interested in updates to the status of an
+ * {@link UpdateComponent}.
+ */
+public interface UpdateStatusListener {
+
+    /**
+     * Called when the status of an update is changed. Note that the
+     * <code>progress</code> parameter may not be used for all statuses, and
+     * will generally only be implemented for those that involve lengthy I/O
+     * operations such as {@link UpdateStatus#RETRIEVING}.
+     *
+     * @param component The component whose status has changed
+     * @param status The current (new) status of the component
+     * @param progress The percentage progress through the current state
+     */
+    void updateStatusChanged(UpdateComponent component, UpdateStatus status, double progress);
+
+}

src/com/dmdirc/updater/retrieving/BaseRetrievalResult.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.retrieving;
+
+import com.dmdirc.updater.checking.UpdateCheckResult;
+
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+import lombok.ToString;
+
+/**
+ * Simple implementation of a {@link UpdateRetrievalResult}.
+ */
+@Getter
+@ToString
+@RequiredArgsConstructor
+@SuppressWarnings("PMD.UnusedPrivateField")
+public class BaseRetrievalResult implements UpdateRetrievalResult {
+
+    /** The check result that triggered this retrieval. */
+    private final UpdateCheckResult checkResult;
+
+    /** Whether or not the retrieval was successful. */
+    private final boolean successful;
+
+}

src/com/dmdirc/updater/UpdateStatus.java → src/com/dmdirc/updater/retrieving/BaseSingleFileResult.java

@@ -20,41 +20,37 @@
  * SOFTWARE.
  */
 
-package com.dmdirc.updater;
+package com.dmdirc.updater.retrieving;
+
+import com.dmdirc.updater.checking.UpdateCheckResult;
+
+import java.io.File;
+
+import lombok.Getter;
+import lombok.ToString;
 
 /**
- * Represents the status of an update.
+ * Simple implementation of a {@link SingleFileRetrievalResult}.
  */
-public enum UpdateStatus {
-
-    /** Update pending. */
-    PENDING("Pending"),
-    /** Update downloading. */
-    DOWNLOADING("Downloading"),
-    /** Update installing. */
-    INSTALLING("Installing"),
-    /** Update installed. */
-    INSTALLED("Installed"),
-    /** Error updating. */
-    ERROR("Error"),
-    /** Update requires restart. */
-    RESTART_NEEDED("Restart needed");
-
-    /** Friendly name. */
-    private final String friendlyName;
+@Getter
+@ToString(callSuper=true)
+@SuppressWarnings("PMD.UnusedPrivateField")
+public class BaseSingleFileResult extends BaseRetrievalResult
+        implements SingleFileRetrievalResult {
+
+    /** The file where the update is located. */
+    private final File file;
 
     /**
-     * Instantiates a new update status.
+     * Creates a new instance of {@link BaseSingleFileResult}.
      *
-     * @param friendlyName Friendly name for the status
+     * @param checkResult The check result that triggered this retrieval
+     * @param file The file containing the update
      */
-    UpdateStatus(final String friendlyName) {
-        this.friendlyName = friendlyName;
-    }
+    public BaseSingleFileResult(final UpdateCheckResult checkResult, final File file) {
+        super(checkResult, true);
 
-    /** {@inheritDoc} */
-    @Override
-    public String toString() {
-        return friendlyName;
+        this.file = file;
     }
+
 }

src/com/dmdirc/updater/retrieving/DownloadRetrievalStrategy.java

@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.retrieving;
+
+import com.dmdirc.updater.UpdateComponent;
+import com.dmdirc.updater.checking.DownloadableUpdate;
+import com.dmdirc.util.io.DownloadListener;
+import com.dmdirc.util.io.Downloader;
+
+import java.io.File;
+import java.io.IOException;
+
+import lombok.AllArgsConstructor;
+import lombok.ListenerSupport;
+import lombok.extern.slf4j.Slf4j;
+
+/**
+ * An {@link UpdateRetrievalStategy} that downloads a file specified in a
+ * {@link DownloadableUpdate}.
+ */
+@Slf4j
+@ListenerSupport(UpdateRetrievalListener.class)
+public class DownloadRetrievalStrategy extends TypeSensitiveRetrievalStrategy<DownloadableUpdate> {
+
+    /** The directory to put temporary update files in. */
+    private final String directory;
+
+    /**
+     * Creates a new {@link DownloadRetrievalStrategy} which will place its
+     * temporary files in the given directory.
+     *
+     * @param directory The directory to use to download files to
+     */
+    public DownloadRetrievalStrategy(final String directory) {
+        super(DownloadableUpdate.class);
+
+        this.directory = directory;
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    protected UpdateRetrievalResult retrieveImpl(final DownloadableUpdate checkResult) {
+        try {
+            final String file = getFileName();
+
+            fireRetrievalProgressChanged(checkResult.getComponent(), 0);
+
+            log.debug("Downloading file from {} to {}", checkResult.getUrl(), file);
+            Downloader.downloadPage(checkResult.getUrl().toString(), file,
+                    new DownloadProgressListener(checkResult.getComponent()));
+
+            fireRetrievalCompleted(checkResult.getComponent());
+
+            return new BaseSingleFileResult(checkResult, new File(file));
+        } catch (IOException ex) {
+            log.warn("I/O exception downloading update from {}", checkResult.getUrl(), ex);
+            fireRetrievalFailed(checkResult.getComponent());
+        }
+
+        return new BaseRetrievalResult(checkResult, false);
+    }
+
+    /**
+     * Creates a random local file name to download the remote file to.
+     *
+     * @return The full, local path to download the remote file to
+     */
+    private String getFileName() {
+        return directory + File.separator + "update."
+                    + Math.round(10000 * Math.random()) + ".tmp";
+    }
+
+    /**
+     * A {@link DownloadListener} which proxies progress updates on to
+     * this strategy's {@link UpdateRetrievalListener}s.
+     */
+    @AllArgsConstructor
+    private class DownloadProgressListener implements DownloadListener {
+
+        /** The component to fire updates for. */
+        private final UpdateComponent component;
+
+        /** {@inheritDoc} */
+        @Override
+        public void downloadProgress(final float percent) {
+            fireRetrievalProgressChanged(component, percent);
+        }
+
+        /** {@inheritDoc} */
+        @Override
+        public void setIndeterminate(final boolean indeterminate) {
+            // Do nothing
+        }
+
+    }
+
+}

src/com/dmdirc/updater/UpdateCheckerListener.java → src/com/dmdirc/updater/retrieving/SingleFileRetrievalResult.java

@@ -20,19 +20,21 @@
  * SOFTWARE.
  */
 
-package com.dmdirc.updater;
+package com.dmdirc.updater.retrieving;
+
+import java.io.File;
 
 /**
- * Update Checker Listeners receive notifications when the status of the update
- * checker changes.
+ * A specialised {@link UpdateRetrievalResult} which specifies a single file
+ * where the update is located.
  */
-public interface UpdateCheckerListener {
+public interface SingleFileRetrievalResult extends UpdateRetrievalResult {
 
     /**
-     * Called when the status of the update checker changes.
+     * Retrieves the location that the update is stored in.
      *
-     * @param newStatus The new status of the update checker
+     * @return The file containing the retrieved update
      */
-    void statusChanged(UpdateChecker.STATE newStatus);
+    File getFile();
 
 }

src/com/dmdirc/updater/retrieving/TypeSensitiveRetrievalStrategy.java

@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.retrieving;
+
+import com.dmdirc.updater.checking.UpdateCheckResult;
+
+import lombok.RequiredArgsConstructor;
+
+/**
+ * Base class for {@link UpdateRetrievalStategy} implementations that can
+ * handle a single subclass of {@link UpdateCheckResult}.
+ *
+ * @param <T> The type of result that this strategy can handle
+ */
+@RequiredArgsConstructor
+public abstract class TypeSensitiveRetrievalStrategy<T extends UpdateCheckResult>
+        implements UpdateRetrievalStategy {
+
+    /** The type of result that this strategy can handle. */
+    private final Class<T> clazz;
+
+    /** {@inheritDoc} */
+    @Override
+    public boolean canHandle(final UpdateCheckResult checkResult) {
+        return clazz.isAssignableFrom(checkResult.getClass());
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    @SuppressWarnings("unchecked")
+    public UpdateRetrievalResult retrieve(final UpdateCheckResult checkResult) {
+        return retrieveImpl((T) checkResult);
+    }
+
+    /**
+     * Retrieves the update associated with the given {@link UpdateCheckResult}.
+     *
+     * @param checkResult The update check result describing the update
+     * requiring retrieval.
+     * @return An {@link UpdateRetrievalResult} which describes the result of
+     * the retrieval, providing information for an
+     * {@link UpdateInstallationStrategy} to use to install the update.
+     * @see #retrieve(com.dmdirc.updater.checking.UpdateCheckResult)
+     */
+    protected abstract UpdateRetrievalResult retrieveImpl(T checkResult);
+
+}

src/com/dmdirc/updater/retrieving/UpdateRetrievalListener.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.retrieving;
+
+import com.dmdirc.updater.UpdateComponent;
+
+/**
+ * Interface for objects interested in the progress of a retrieval attempt
+ * performed by an {@link UpdateRetrievalStategy}.
+ */
+public interface UpdateRetrievalListener {
+
+    /**
+     * Called when the progress of a retrieval operation has changed.
+     *
+     * @param component The component being retrieved
+     * @param progress The percentage progress completed (0-100)
+     */
+    void retrievalProgressChanged(UpdateComponent component, double progress);
+
+    /**
+     * Called when a retrieval has failed.
+     *
+     * @param component The component that failed to install
+     */
+    void retrievalFailed(UpdateComponent component);
+
+    /**
+     * Called when a retrieval has finished.
+     *
+     * @param component The component that was successfully installed
+     */
+    void retrievalCompleted(UpdateComponent component);
+
+}

src/com/dmdirc/updater/UpdateListener.java → src/com/dmdirc/updater/retrieving/UpdateRetrievalResult.java

@@ -20,27 +20,28 @@
  * SOFTWARE.
  */
 
-package com.dmdirc.updater;
+package com.dmdirc.updater.retrieving;
+
+import com.dmdirc.updater.checking.UpdateCheckResult;
 
 /**
- * Defines the method that must be implemented by update listeners.
+ * Describes the result of a retrieval operation by an
+ * {@link UpdateRetrievalStategy}.
  */
-public interface UpdateListener {
+public interface UpdateRetrievalResult {
 
     /**
-     * Called when the state of the update has changed.
+     * Gets the check result which was used to perform the retrieval.
      *
-     * @param update The update in question
-     * @param status The new status of the update
+     * @return The check result used to perform the retrieval
      */
-    void updateStatusChange(Update update, UpdateStatus status);
+    UpdateCheckResult getCheckResult();
 
     /**
-     * Called when the progress of the current update state has changed.
+     * Determines whether the retrieval was successful or not.
      *
-     * @param update The update in question
-     * @param progress The progress (as a percentage) of the update
+     * @return True if the retrieval worked, false otherwise
      */
-    void updateProgressChange(Update update, float progress);
+    boolean isSuccessful();
 
 }

src/com/dmdirc/updater/retrieving/UpdateRetrievalStategy.java

@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2006-2012 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.updater.retrieving;
+
+import com.dmdirc.updater.checking.UpdateCheckResult;
+import com.dmdirc.updater.checking.UpdateCheckStrategy;
+import com.dmdirc.updater.installing.UpdateInstallationStrategy;
+
+/**
+ * Defines a strategy for retrieving updated files that have been identified by
+ * an {@link UpdateCheckStrategy}. Retrieval strategies will place updates in
+ * a temporary location on disk for use by an {@link UpdateInstallationStrategy}.
+ */
+public interface UpdateRetrievalStategy {
+
+    /**
+     * Determines whether this strategy can handle retrieving the given update.
+     *
+     * @param checkResult The update check result describing the update
+     * requiring retrieval.
+     * @return True if this strategy can handle the update; false otherwise
+     */
+    boolean canHandle(UpdateCheckResult checkResult);
+
+    /**
+     * Retrieves the update associated with the given {@link UpdateCheckResult}.
+     *
+     * @param checkResult The update check result describing the update
+     * requiring retrieval.
+     * @return An {@link UpdateRetrievalResult} which describes the result of
+     * the retrieval, providing information for an
+     * {@link UpdateInstallationStrategy} to use to install the update.
+     */
+    UpdateRetrievalResult retrieve(UpdateCheckResult checkResult);
+
+    /**
+     * Adds a new status listener to this strategy.
+     *
+     * @param listener The listener to be registered
+     */
+    void addUpdateRetrievalListener(UpdateRetrievalListener listener);
+
+    /**
+     * Removes the given listener from this strategy.
+     *
+     * @param listener The listener to be removed
+     */
+    void removeUpdateRetrievalListener(UpdateRetrievalListener listener);
+
+}