component.java

This is a resource based on j2me embedded,if you dont understand,you can connection with me .

/*
 * @(#)Component.java	1.53 06/10/10
 *
 * Copyright  1990-2008 Sun Microsystems, Inc. All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
 * 
 * This program 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. 
 * 
 * This program 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 at /legal/license.txt). 
 * 
 * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa
 * Clara, CA 95054 or visit www.sun.com if you need additional
 * information or have any questions. 
 *
 */
package java.awt;

import java.io.PrintStream;
import java.io.PrintWriter;
import java.util.Vector;
import java.util.Locale;
import java.util.EventListener;
import java.util.Timer;
import java.util.TimerTask;
import java.awt.im.InputContext;
import java.awt.im.InputMethodRequests;
import java.awt.image.ImageObserver;
import java.awt.image.ImageProducer;
import java.awt.image.ColorModel;
import java.awt.image.VolatileImage;
import java.awt.event.*;
import java.io.Serializable;
import java.io.ObjectOutputStream;
import java.io.ObjectInputStream;
import java.io.IOException;
import java.beans.PropertyChangeListener;
import java.security.AccessController;
import sun.awt.NullGraphics;
import sun.awt.ConstrainableGraphics;
import sun.awt.AppContext;
import sun.awt.SunToolkit;
import sun.security.action.GetPropertyAction;
import java.util.Set;
import java.util.Iterator;
import java.util.HashSet;
import java.util.Collections;

/**
 * A <em>component</em> is an object having a graphical representation
 * that can be displayed on the screen and that can interact with the
 * user. Examples of components are the buttons, checkboxes, and scrollbars
 * of a typical graphical user interface. <p>
 * The <code>Component</code> class is the abstract superclass of
 * the nonmenu-related Abstract Window Toolkit components. Class
 * <code>Component</corede> can also be extended directly to create a
 * lightweight component. A lightweight component is a component that is
 * not associated with a native opaque window.
 *
 * <p>
 * <a name="restrictions">
 * <h4>Restrictions</h4>
 * <em>
 * Implementations of Component in Personal Basis Profile exhibit
 * certain restrictions, specifically:
 * <ul>
 * <li> An implementation may prohibit setting the cursor.  In such
 * a case, attempts to set the cursor will fail silently.
 * See:
 * <ul>
 * <li> {@link #setCursor}
 * </ul>
 * </ul>
 * </em>
 * @version 1.11, 01/16/02
 * @author Nicholas Allen
 */
public abstract class Component implements ImageObserver,
        Serializable {
    /**
     * The parent of the object. It may be null for top-level components.
     * @see #getParent
     */
    transient Container parent;
    /**
     * The x position of the component in the parent's coordinate system.
     *
     * @serial
     * @see #getLocation
     */
    int x;
    /**
     * The y position of the component in the parent's coordinate system.
     *
     * @serial
     * @see #getLocation
     */
    int y;
    /**
     * The width of the component.
     *
     * @serial
     * @see #getSize
     */
    int width;
    /**
     * The height of the component.
     *
     * @serial
     * @see #getSize
     */
    int height;
    /**
     * The foreground color for this component.
     * foreground color can be null.
     *
     * @serial
     * @see #getForeground
     * @see #setForeground
     */
    Color	foreground;
    /**
     * The background color for this component.
     * background can be null.
     *
     * @serial
     * @see #getBackground
     * @see #setBackground
     */
    Color	background;
    /**
     * The font used by this component.
     * The font can be null.
     *
     * @serial
     * @see #getFont
     * @see #setFont
     */
    Font	font;
    /**
     * The cursor displayed when pointer is over this component.
     * This value can be null.
     *
     * @serial
     * @see #getCursor
     * @see #setCursor
     */
    Cursor	cursor;
    /**
     * The locale for the component.
     *
     * @serial
     * @see #getLocale
     * @see #setLocale
     */
    Locale      locale;
    /**
     * A reference to a GraphicsConfiguration object
     * used to describe the characteristics of a graphics
     * destination.
     * This value can be null.
     *
     * @since 1.3
     * @serial
     * @see java.awt.GraphicsConfiguration
     * @see #getGraphicsConfiguration
     */
    //transient GraphicsConfiguration graphicsConfig = null;

    // ### Serialization difference
    // No field GraphicsConfiguration graphicsConfig

    /**
     * True when the object should ignore all repaint events.
     *
     * @since 1.4
     * @serial
     * @see #setIgnoreRepaint
     * @see #getIgnoreRepaint
     */
    boolean ignoreRepaint = false;

    /**
     * True when the object is visible. An object that is not
     * visible is not drawn on the screen.
     *
     * @serial
     * @see #isVisible
     * @see #setVisible
     */
    boolean visible = true;
    /**
     * True when the object is enabled. An object that is not
     * enabled does not interact with the user.
     *
     * @serial
     * @see #isEnabled
     * @see #setEnabled
     */
    boolean enabled = true;
    /**
     * True when the object is displayable. This field is necessary
     * because peers are not used in basis profile.
     *
     * @see #isDisplayable
     */

    transient boolean displayable;
    /**
     * True when the object is valid. An invalid object needs to
     * be layed out. This flag is set to false when the object
     * size is changed.
     *
     * @serial
     * @see #isValid
     * @see #validate
     * @see #invalidate
     */
    boolean valid = false;
    /**
     * A components name.
     * This field can be null.
     *
     * @serial
     * @see getName()
     * @see setName(String)
     */
    private String name;
    /**
     * A bool to determine whether the name has
     * been set explicitly. nameExplicitlySet will
     * be false if the name has not been set and
     * true if it has.
     *
     * @serial
     * @see getName()
     * @see setName(String)
     */
    private boolean nameExplicitlySet = false;
    /**
     * The locking object for AWT component-tree and layout operations.
     *
     * @see #getTreeLock
     */
    static final Object LOCK = new AWTTreeLock();
    static class AWTTreeLock {}
    /**
     * Internal, cached size information.
     * (This field perhaps should have been transient).
     *
     * @serial
     */
    Dimension minSize;
    /** Internal, cached size information
     * (This field perhaps should have been transient).
     *
     * @serial
     */
    Dimension prefSize;
    boolean newEventsOnly = false;
    transient ComponentListener componentListener;
    transient FocusListener focusListener;
    transient KeyListener keyListener;
    transient MouseListener mouseListener;
    transient MouseMotionListener mouseMotionListener;
    transient MouseWheelListener mouseWheelListener;
    transient InputMethodListener inputMethodListener;

    /**
     * The eventMask is ONLY set by subclasses via enableEvents.
     * The mask should NOT be set when listeners are registered
     * so that we can distinguish the difference between when
     * listeners request events and subclasses request them.
     * One bit is used to indicate whether input methods are
     * enabled; this bit is set by enableInputMethods and is
     * on by default.
     *
     * @serial
     * @see enableInputMethods()
     */
    long eventMask = AWTEvent.INPUT_METHODS_ENABLED_MASK;
    /**
     * Static properties for incremental drawing.
     * @see #imageUpdate
     */
    static boolean isInc;
    static int incRate;
    static {
        String s = (String) AccessController.doPrivileged(
                new GetPropertyAction("awt.image.incrementaldraw"));
        isInc = (s == null || s.equals("true"));
        s = (String) AccessController.doPrivileged(
                    new GetPropertyAction("awt.image.redrawrate"));
        incRate = (s != null) ? Integer.parseInt(s) : 100;
    }
    /**
     * Ease-of-use constant for <code>getAlignmentY()</code>.  Specifies an
     * alignment to the top of the component.
     * @see     #getAlignmentY
     */
    public static final float TOP_ALIGNMENT = 0.0f;
    /**
     * Ease-of-use constant for <code>getAlignmentY</code> and
     * <code>getAlignmentX</code>. Specifies an alignment to
     * the center of the component
     * @see     #getAlignmentX
     * @see     #getAlignmentY
     */
    public static final float CENTER_ALIGNMENT = 0.5f;
    /**
     * Ease-of-use constant for <code>getAlignmentY</code>.  Specifies an
     * alignment to the bottom of the component.
     * @see     #getAlignmentY
     */
    public static final float BOTTOM_ALIGNMENT = 1.0f;
    /**
     * Ease-of-use constant for <code>getAlignmentX</code>.  Specifies an
     * alignment to the left side of the component.
     * @see     #getAlignmentX
     */
    public static final float LEFT_ALIGNMENT = 0.0f;
    /**
     * Ease-of-use constant for <code>getAlignmentX</code>.  Specifies an
     * alignment to the right side of the component.
     * @see     #getAlignmentX
     */
    public static final float RIGHT_ALIGNMENT = 1.0f;
    /*
     * JDK 1.1 serialVersionUID
     */
    private static final long serialVersionUID = -7644114512714619750L;
    /**
     * If any PropertyChangeListeners have been registered, the
     * changeSupport field describes them.
     *
     * @serial
     * @since 1.2
     * @see addPropertyChangeListener
     * @see removePropertyChangeListener
     * @see firePropertyChange
     */
    private java.beans.PropertyChangeSupport changeSupport;
    /** Internal, constants for serialization */
    final static String actionListenerK = "actionL";
    final static String adjustmentListenerK = "adjustmentL";
    final static String componentListenerK = "componentL";
    final static String containerListenerK = "containerL";
    final static String focusListenerK = "focusL";
    final static String itemListenerK = "itemL";
    final static String keyListenerK = "keyL";
    final static String mouseListenerK = "mouseL";
    final static String mouseMotionListenerK = "mouseMotionL";
    final static String mouseWheelListenerK = "mouseWheelL";
    final static String textListenerK = "textL";
    final static String windowListenerK = "windowL";
    final static String inputMethodListenerK = "inputMethodL";
    boolean isPacked = false;
    private static Timer TIMER;

    /**
     * The <code>AppContext</code> of the component.  This is set in
     * the constructor and never changes.