DMDirc-Plugins/ui_swing/src/main/java/com/dmdirc/addons/ui_swing/components/renderers/PropertyListCellRenderer.java

/*
 * Copyright (c) 2006-2017 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.components.renderers;

import java.lang.reflect.Method;

import javax.swing.ListCellRenderer;

/**
 * Displays the text from the specified getter as the list cell. If the getter does not exist it
 * will fall back to the toString method.
 *
 * @param <E> the type of values this renderer can be used for
 */
public class PropertyListCellRenderer<E> extends MethodListCellRenderer<E> {

    /** Serial version UID. */
    private static final long serialVersionUID = 1L;

    /**
     * Creates a renderer.
     *
     * @param parentRenderer Parent renderer
     * @param type           Type of object to be rendered
     * @param property       The name of the property to use when rendering. The type must implement
     *                       a 'get' method for this property that returns a string.
     */
    public PropertyListCellRenderer(final ListCellRenderer<? super E> parentRenderer,
            final Class<? super E> type, final String property) {
        super(parentRenderer, getMethod(property, type));
    }

    private static <E> Method getMethod(final String property, final Class<E> type) {
        Method readMethod;
        try {
            readMethod = type.getMethod("get" + (property.substring(0, 1).toUpperCase() + property.
                    substring(1)));
        } catch (NoSuchMethodException | SecurityException ex) {
            readMethod = getToStringMethod(type);
        }
        if (readMethod == null || readMethod.getReturnType() != String.class) {
            readMethod = getToStringMethod(type);
        }
        return readMethod;
    }

    private static <E> Method getToStringMethod(final Class<E> type) {
        try {
            return type.getMethod("toString");
        } catch (NoSuchMethodException | SecurityException ex1) {
            throw new IllegalStateException("Unable to access toString method", ex1);
        }
    }

}