Introduce a DialogProvider.

This fixes the issues with injection of dialogs and the behaviour of @Singleton.

Move the swing injection related classes into a new package (a new DialogModule
will follow shortly to make use of the DialogProvider).

Also introduce a SwingPreconditions class for asserting method calls are made
on/off the EDT.

Change-Id: I92010f61f2289579603a239ab46b0a304799dedc
Reviewed-on: http://gerrit.dmdirc.com/3044
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Greg Holmes <greg@dmdirc.com>

src/com/dmdirc/addons/activewindow/ActiveWindowModule.java

@@ -22,7 +22,7 @@
 
 package com.dmdirc.addons.activewindow;
 
-import com.dmdirc.addons.ui_swing.SwingModule;
+import com.dmdirc.addons.ui_swing.injection.SwingModule;
 
 import dagger.Module;
 

src/com/dmdirc/addons/dcc/DCCPluginModule.java

@@ -22,7 +22,7 @@
 
 package com.dmdirc.addons.dcc;
 
-import com.dmdirc.addons.ui_swing.SwingModule;
+import com.dmdirc.addons.ui_swing.injection.SwingModule;
 import com.dmdirc.plugins.PluginInfo;
 
 import dagger.Module;

src/com/dmdirc/addons/lagdisplay/LagDisplayModule.java

@@ -22,7 +22,7 @@
 
 package com.dmdirc.addons.lagdisplay;
 
-import com.dmdirc.addons.ui_swing.SwingModule;
+import com.dmdirc.addons.ui_swing.injection.SwingModule;
 
 import dagger.Module;
 import dagger.Provides;

src/com/dmdirc/addons/serverlistdialog/ServerListModule.java

@@ -22,7 +22,7 @@
 
 package com.dmdirc.addons.serverlistdialog;
 
-import com.dmdirc.addons.ui_swing.SwingModule;
+import com.dmdirc.addons.ui_swing.injection.SwingModule;
 
 import dagger.Module;
 

src/com/dmdirc/addons/ui_swing/SwingController.java

@@ -46,6 +46,7 @@ import com.dmdirc.addons.ui_swing.dialogs.error.ErrorListDialog;
 import com.dmdirc.addons.ui_swing.dialogs.prefs.SwingPreferencesDialog;
 import com.dmdirc.addons.ui_swing.dialogs.serversetting.ServerSettingsDialog;
 import com.dmdirc.addons.ui_swing.dialogs.url.URLDialog;
+import com.dmdirc.addons.ui_swing.injection.SwingModule;
 import com.dmdirc.config.prefs.PluginPreferencesCategory;
 import com.dmdirc.config.prefs.PreferencesCategory;
 import com.dmdirc.config.prefs.PreferencesDialogModel;

src/com/dmdirc/addons/ui_swing/SwingPreconditions.java

@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2006-2014 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.addons.ui_swing;
+
+import com.google.common.base.Preconditions;
+
+import javax.swing.SwingUtilities;
+
+/**
+ * Swing-specific preconditions.
+ */
+public final class SwingPreconditions {
+
+    private SwingPreconditions() {
+        // Shouldn't be instansiated.
+    }
+
+    /**
+     * Checks that the method is called on the Swing EDT.
+     *
+     * @throw IllegalStateException if the method is called from another thread.
+     */
+    public static void checkOnEDT() {
+        Preconditions.checkState(SwingUtilities.isEventDispatchThread(),
+                "Must be called on the event despatch thread");
+    }
+
+    /**
+     * Checks that the method is NOT called on the Swing EDT.
+     *
+     * @throw IllegalStateException if the method is called from the EDT.
+     */
+    public static void checkNotOnEDT() {
+        Preconditions.checkState(!SwingUtilities.isEventDispatchThread(),
+                "Must not be called ont he event despatch thread");
+    }
+
+}

src/com/dmdirc/addons/ui_swing/injection/DialogProvider.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2006-2014 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.addons.ui_swing.injection;
+
+import static com.dmdirc.addons.ui_swing.SwingPreconditions.checkOnEDT;
+import com.dmdirc.addons.ui_swing.dialogs.StandardDialog;
+
+import java.awt.event.WindowAdapter;
+import java.awt.event.WindowEvent;
+import javax.inject.Provider;
+
+/**
+ * Simple provider for {@link StandardDialog} based windows.
+ *
+ * <p>This provider will cache instances that are created until the windows are closed. Once a
+ * window has been closed, the next call to {@link #get()} or {@link #displayOrRequestFocus()}
+ * will result in a new instance being created.
+ *
+ * @param <T> The type of dialog that will be managed.
+ */
+public class DialogProvider<T extends StandardDialog> {
+
+    /** Provider used to generate new instances. */
+    private final Provider<T> provider;
+    /** The existing instance being displayed, if any. */
+    private T instance;
+
+    /**
+     * Creates a new instance of {@link DialogProvider}.
+     *
+     * @param provider The provider to use to generate new instances of the dialog, when required.
+     */
+    public DialogProvider(final Provider<T> provider) {
+        this.provider = provider;
+    }
+
+    /**
+     * Gets an instance of the dialog provided by this class.
+     *
+     * <p>If there is an existing instance that hasn't been closed, it will be returned. Otherwise
+     * a new instance will be created and returned. New instances will not be automatically be
+     * displayed to the user - use {@link #displayOrRequestFocus()} to do so.
+     *
+     * <p>This method <em>must</em> be called on the Event Despatch Thread.
+     *
+     * @return An instance of the dialog.
+     */
+    public T get() {
+        checkOnEDT();
+        if (instance == null) {
+            instance = provider.get();
+            instance.addWindowListener(new Listener());
+        }
+        return instance;
+    }
+
+    /**
+     * Ensures the dialog is visible to the user.
+     *
+     * <p>If no dialog currently exists, a new one will be created and displayed to the user. If
+     * a dialog existed prior to this method being invoked, it will request focus to bring it to
+     * the user's attention.
+     *
+     * <p>This method <em>must</em> be called on the Event Despatch Thread.
+     */
+    public void displayOrRequestFocus() {
+        checkOnEDT();
+        get().displayOrRequestFocus();
+    }
+
+    /**
+     * Listens to window closing events to remove the cached instance of the dialog.
+     */
+    private class Listener extends WindowAdapter {
+
+        @Override
+        public void windowClosing(final WindowEvent e) {
+            super.windowClosing(e);
+            instance = null;
+        }
+
+    }
+
+}

src/com/dmdirc/addons/ui_swing/SwingModule.java → src/com/dmdirc/addons/ui_swing/injection/SwingModule.java

@@ -20,11 +20,17 @@
  * SOFTWARE.
  */
 
-package com.dmdirc.addons.ui_swing;
+package com.dmdirc.addons.ui_swing.injection;
 
 import com.dmdirc.ClientModule;
 import com.dmdirc.ClientModule.GlobalConfig;
 import com.dmdirc.ServerManager;
+import com.dmdirc.addons.ui_swing.MainFrame;
+import com.dmdirc.addons.ui_swing.QuitWorker;
+import com.dmdirc.addons.ui_swing.SwingController;
+import com.dmdirc.addons.ui_swing.SwingManager;
+import com.dmdirc.addons.ui_swing.SwingWindowFactory;
+import com.dmdirc.addons.ui_swing.UIUtilities;
 import com.dmdirc.addons.ui_swing.commands.ChannelSettings;
 import com.dmdirc.addons.ui_swing.commands.Input;
 import com.dmdirc.addons.ui_swing.commands.PopInCommand;