/*

 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package javax.swing.text;

import java.awt.event.ActionEvent;

import java.awt.KeyboardFocusManager;

import java.awt.Component;

import java.util.Hashtable;

import java.util.Enumeration;

import javax.swing.Action;

import javax.swing.AbstractAction;

import javax.swing.KeyStroke;

/**

 * An Action implementation useful for key bindings that are

 * shared across a number of different text components.  Because

 * the action is shared, it must have a way of getting it's

 * target to act upon.  This class provides support to try and

 * find a text component to operate on.  The preferred way of

 * getting the component to act upon is through the ActionEvent

 * that is received.  If the Object returned by getSource can

 * be narrowed to a text component, it will be used.  If the

 * action event is null or can't be narrowed, the last focused

 * text component is tried.  This is determined by being

 * used in conjunction with a JTextController which

 * arranges to share that information with a TextAction.

 * <p>

 * <strong>Warning:</strong>

 * Serialized objects of this class will not be compatible with

 * future Swing releases. The current serialization support is

 * appropriate for short term storage or RMI between applications running

 * the same version of Swing.  As of 1.4, support for long term storage

 * of all JavaBeans™

 * has been added to the <code>java.beans</code> package.

 * Please see {@link java.beans.XMLEncoder}.

 *

 * @author  Timothy Prinzing

 */

@SuppressWarnings("serial") // Same-version serialization only

public abstract class TextAction extends AbstractAction {

    /**

     * Creates a new JTextAction object.

     *

     * @param name the name of the action

     */

    public TextAction(String name) {

        super(name);

    }

    /**

     * Determines the component to use for the action.

     * This if fetched from the source of the ActionEvent

     * if it's not null and can be narrowed.  Otherwise,

     * the last focused component is used.

     *

     * @param e the ActionEvent

     * @return the component

     */

    protected final JTextComponent getTextComponent(ActionEvent e) {

        if (e != null) {

            Object o = e.getSource();

            if (o instanceof JTextComponent) {

                return (JTextComponent) o;

            }

        }

        return getFocusedComponent();

    }

    /**

     * Takes one list of

     * commands and augments it with another list

     * of commands.  The second list takes precedence

     * over the first list; that is, when both lists

     * contain a command with the same name, the command

     * from the second list is used.

     *

     * @param list1 the first list, may be empty but not

     *              <code>null</code>

     * @param list2 the second list, may be empty but not

     *              <code>null</code>

     * @return the augmented list

     */

    public static final Action[] augmentList(Action[] list1, Action[] list2) {

        Hashtable<String, Action> h = new Hashtable<String, Action>();

        for (Action a : list1) {

            String value = (String)a.getValue(Action.NAME);

            h.put((value!=null ? value:""), a);

        }

        for (Action a : list2) {

            String value = (String)a.getValue(Action.NAME);

            h.put((value!=null ? value:""), a);

        }

        Action[] actions = new Action[h.size()];

        int index = 0;

        for (Enumeration e = h.elements() ; e.hasMoreElements() ;) {

            actions[index++] = (Action) e.nextElement();

        }

        return actions;

    }

    /**

     * Fetches the text component that currently has focus.

     * This allows actions to be shared across text components

     * which is useful for key-bindings where a large set of

     * actions are defined, but generally used the same way

     * across many different components.

     *

     * @return the component

     */

    protected final JTextComponent getFocusedComponent() {

        return JTextComponent.getFocusedComponent();

    }

}