/*

 * Copyright (c) 1997, 2007, 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package javax.swing;

import java.awt.*;

import java.awt.event.*;

import java.beans.*;

import java.util.Hashtable;

import java.util.Enumeration;

import java.io.Serializable;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

import java.security.AccessController;

import javax.swing.event.SwingPropertyChangeSupport;

import sun.security.action.GetPropertyAction;

/**

 * This class provides default implementations for the JFC <code>Action</code>

 * interface. Standard behaviors like the get and set methods for

 * <code>Action</code> object properties (icon, text, and enabled) are defined

 * here. The developer need only subclass this abstract class and

 * define the <code>actionPerformed</code> method.

 * <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<sup><font size="-2">TM</font></sup>

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

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

 *

 * @author Georges Saab

 * @see Action

 */

public abstract class AbstractAction implements Action, Cloneable, Serializable

{

    /**

     * Whether or not actions should reconfigure all properties on null.

     */

    private static Boolean RECONFIGURE_ON_NULL;

    /**

     * Specifies whether action is enabled; the default is true.

     */

    protected boolean enabled = true;

    /**

     * Contains the array of key bindings.

     */

    private transient ArrayTable arrayTable;

    /**

     * Whether or not to reconfigure all action properties from the

     * specified event.

     */

    static boolean shouldReconfigure(PropertyChangeEvent e) {

        if (e.getPropertyName() == null) {

            synchronized(AbstractAction.class) {

                if (RECONFIGURE_ON_NULL == null) {

                    RECONFIGURE_ON_NULL = Boolean.valueOf(

                        AccessController.doPrivileged(new GetPropertyAction(

                        "swing.actions.reconfigureOnNull", "false")));

                }

                return RECONFIGURE_ON_NULL;

            }

        }

        return false;

    }

    /**

     * Sets the enabled state of a component from an Action.

     *

     * @param c the Component to set the enabled state on

     * @param a the Action to set the enabled state from, may be null

     */

    static void setEnabledFromAction(JComponent c, Action a) {

        c.setEnabled((a != null) ? a.isEnabled() : true);

    }

    /**

     * Sets the tooltip text of a component from an Action.

     *

     * @param c the Component to set the tooltip text on

     * @param a the Action to set the tooltip text from, may be null

     */

    static void setToolTipTextFromAction(JComponent c, Action a) {

        c.setToolTipText(a != null ?

                         (String)a.getValue(Action.SHORT_DESCRIPTION) : null);

    }

    static boolean hasSelectedKey(Action a) {

        return (a != null && a.getValue(Action.SELECTED_KEY) != null);

    }

    static boolean isSelected(Action a) {

        return Boolean.TRUE.equals(a.getValue(Action.SELECTED_KEY));

    }

    /**

     * Creates an {@code Action}.

     */

    public AbstractAction() {

    }

    /**

     * Creates an {@code Action} with the specified name.

     *

     * @param name the name ({@code Action.NAME}) for the action; a

     *        value of {@code null} is ignored

     */

    public AbstractAction(String name) {

        putValue(Action.NAME, name);

    }

    /**

     * Creates an {@code Action} with the specified name and small icon.

     *

     * @param name the name ({@code Action.NAME}) for the action; a

     *        value of {@code null} is ignored

     * @param icon the small icon ({@code Action.SMALL_ICON}) for the action; a

     *        value of {@code null} is ignored

     */

    public AbstractAction(String name, Icon icon) {

        this(name);

        putValue(Action.SMALL_ICON, icon);

    }

    /**

     * Gets the <code>Object</code> associated with the specified key.

     *

     * @param key a string containing the specified <code>key</code>

     * @return the binding <code>Object</code> stored with this key; if there

     *          are no keys, it will return <code>null</code>

     * @see Action#getValue

     */

    public Object getValue(String key) {

        if (key == "enabled") {

            return enabled;

        }

        if (arrayTable == null) {

            return null;

        }

        return arrayTable.get(key);

    }

    /**

     * Sets the <code>Value</code> associated with the specified key.

     *

     * @param key  the <code>String</code> that identifies the stored object

     * @param newValue the <code>Object</code> to store using this key

     * @see Action#putValue

     */

    public void putValue(String key, Object newValue) {

        Object oldValue = null;

        if (key == "enabled") {

            // Treat putValue("enabled") the same way as a call to setEnabled.

            // If we don't do this it means the two may get out of sync, and a

            // bogus property change notification would be sent.

            //

            // To avoid dependencies between putValue & setEnabled this

            // directly changes enabled. If we instead called setEnabled

            // to change enabled, it would be possible for stack

            // overflow in the case where a developer implemented setEnabled

            // in terms of putValue.

            if (newValue == null || !(newValue instanceof Boolean)) {

                newValue = false;

            }

            oldValue = enabled;

            enabled = (Boolean)newValue;

        } else {

            if (arrayTable == null) {

                arrayTable = new ArrayTable();

            }

            if (arrayTable.containsKey(key))

                oldValue = arrayTable.get(key);

            // Remove the entry for key if newValue is null

            // else put in the newValue for key.

            if (newValue == null) {

                arrayTable.remove(key);

            } else {

                arrayTable.put(key,newValue);

            }

        }

        firePropertyChange(key, oldValue, newValue);

    }

    /**

     * Returns true if the action is enabled.

     *

     * @return true if the action is enabled, false otherwise

     * @see Action#isEnabled

     */

    public boolean isEnabled() {

        return enabled;

    }

    /**

     * Sets whether the {@code Action} is enabled. The default is {@code true}.

     *

     * @param newValue  {@code true} to enable the action, {@code false} to

     *                  disable it

     * @see Action#setEnabled

     */

    public void setEnabled(boolean newValue) {

        boolean oldValue = this.enabled;

        if (oldValue != newValue) {

            this.enabled = newValue;

            firePropertyChange("enabled",

                               Boolean.valueOf(oldValue), Boolean.valueOf(newValue));

        }

    }

    /**

     * Returns an array of <code>Object</code>s which are keys for

     * which values have been set for this <code>AbstractAction</code>,

     * or <code>null</code> if no keys have values set.

     * @return an array of key objects, or <code>null</code> if no

     *                  keys have values set

     * @since 1.3

     */

    public Object[] getKeys() {

        if (arrayTable == null) {

            return null;

        }

        Object[] keys = new Object[arrayTable.size()];

        arrayTable.getKeys(keys);

        return keys;

    }

    /**

     * If any <code>PropertyChangeListeners</code> have been registered, the

     * <code>changeSupport</code> field describes them.

     */

    protected SwingPropertyChangeSupport changeSupport;

    /**

     * Supports reporting bound property changes.  This method can be called

     * when a bound property has changed and it will send the appropriate

     * <code>PropertyChangeEvent</code> to any registered

     * <code>PropertyChangeListeners</code>.

     */

    protected void firePropertyChange(String propertyName, Object oldValue, Object newValue) {

        if (changeSupport == null ||

            (oldValue != null && newValue != null && oldValue.equals(newValue))) {

            return;

        }

        changeSupport.firePropertyChange(propertyName, oldValue, newValue);

    }

    /**

     * Adds a <code>PropertyChangeListener</code> to the listener list.

     * The listener is registered for all properties.

     * <p>

     * A <code>PropertyChangeEvent</code> will get fired in response to setting

     * a bound property, e.g. <code>setFont</code>, <code>setBackground</code>,

     * or <code>setForeground</code>.

     * Note that if the current component is inheriting its foreground,

     * background, or font from its container, then no event will be

     * fired in response to a change in the inherited property.

     *

     * @param listener  The <code>PropertyChangeListener</code> to be added

     *

     * @see Action#addPropertyChangeListener

     */

    public synchronized void addPropertyChangeListener(PropertyChangeListener listener) {

        if (changeSupport == null) {

            changeSupport = new SwingPropertyChangeSupport(this);

        }

        changeSupport.addPropertyChangeListener(listener);

    }

    /**

     * Removes a <code>PropertyChangeListener</code> from the listener list.

     * This removes a <code>PropertyChangeListener</code> that was registered

     * for all properties.

     *

     * @param listener  the <code>PropertyChangeListener</code> to be removed

     *

     * @see Action#removePropertyChangeListener

     */

    public synchronized void removePropertyChangeListener(PropertyChangeListener listener) {

        if (changeSupport == null) {

            return;

        }

        changeSupport.removePropertyChangeListener(listener);

    }

    /**

     * Returns an array of all the <code>PropertyChangeListener</code>s added

     * to this AbstractAction with addPropertyChangeListener().

     *

     * @return all of the <code>PropertyChangeListener</code>s added or an empty

     *         array if no listeners have been added

     * @since 1.4

     */

    public synchronized PropertyChangeListener[] getPropertyChangeListeners() {

        if (changeSupport == null) {

            return new PropertyChangeListener[0];

        }

        return changeSupport.getPropertyChangeListeners();

    }

    /**

     * Clones the abstract action. This gives the clone

     * its own copy of the key/value list,

     * which is not handled for you by <code>Object.clone()</code>.

     **/

    protected Object clone() throws CloneNotSupportedException {

        AbstractAction newAction = (AbstractAction)super.clone();

        synchronized(this) {

            if (arrayTable != null) {

                newAction.arrayTable = (ArrayTable)arrayTable.clone();

            }

        }

        return newAction;

    }

    private void writeObject(ObjectOutputStream s) throws IOException {

        // Store the default fields

        s.defaultWriteObject();

        // And the keys

        ArrayTable.writeArrayTable(s, arrayTable);

    }

    private void readObject(ObjectInputStream s) throws ClassNotFoundException,

        IOException {

        s.defaultReadObject();

        for (int counter = s.readInt() - 1; counter >= 0; counter--) {

            putValue((String)s.readObject(), s.readObject());

        }

    }

}