/*

 * Copyright 1996-2007 Sun Microsystems, Inc.  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.  Sun designates this

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

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package java.awt;

import java.util.EventObject;

import java.awt.event.*;

import java.awt.peer.ComponentPeer;

import java.awt.peer.LightweightPeer;

import java.lang.reflect.Field;

import sun.awt.AWTAccessor;

/**

 * The root event class for all AWT events.

 * This class and its subclasses supercede the original

 * java.awt.Event class.

 * Subclasses of this root AWTEvent class defined outside of the

 * java.awt.event package should define event ID values greater than

 * the value defined by RESERVED_ID_MAX.

 * <p>

 * The event masks defined in this class are needed by Component subclasses

 * which are using Component.enableEvents() to select for event types not

 * selected by registered listeners. If a listener is registered on a

 * component, the appropriate event mask is already set internally by the

 * component.

 * <p>

 * The masks are also used to specify to which types of events an

 * AWTEventListener should listen. The masks are bitwise-ORed together

 * and passed to Toolkit.addAWTEventListener.

 *

 * @see Component#enableEvents

 * @see Toolkit#addAWTEventListener

 *

 * @see java.awt.event.ActionEvent

 * @see java.awt.event.AdjustmentEvent

 * @see java.awt.event.ComponentEvent

 * @see java.awt.event.ContainerEvent

 * @see java.awt.event.FocusEvent

 * @see java.awt.event.InputMethodEvent

 * @see java.awt.event.InvocationEvent

 * @see java.awt.event.ItemEvent

 * @see java.awt.event.HierarchyEvent

 * @see java.awt.event.KeyEvent

 * @see java.awt.event.MouseEvent

 * @see java.awt.event.MouseWheelEvent

 * @see java.awt.event.PaintEvent

 * @see java.awt.event.TextEvent

 * @see java.awt.event.WindowEvent

 *

 * @author Carl Quinn

 * @author Amy Fowler

 * @since 1.1

 */

public abstract class AWTEvent extends EventObject {

    private byte bdata[];

    /**

     * The event's id.

     * @serial

     * @see #getID()

     * @see #AWTEvent

     */

    protected int id;

    /**

     * Controls whether or not the event is sent back down to the peer once the

     * source has processed it - false means it's sent to the peer; true means

     * it's not. Semantic events always have a 'true' value since they were

     * generated by the peer in response to a low-level event.

     * @serial

     * @see #consume

     * @see #isConsumed

     */

    protected boolean consumed = false;

    transient boolean focusManagerIsDispatching = false;

    transient boolean isPosted;

    /**

     * The event mask for selecting component events.

     */

    public final static long COMPONENT_EVENT_MASK = 0x01;

    /**

     * The event mask for selecting container events.

     */

    public final static long CONTAINER_EVENT_MASK = 0x02;

    /**

     * The event mask for selecting focus events.

     */

    public final static long FOCUS_EVENT_MASK = 0x04;

    /**

     * The event mask for selecting key events.

     */

    public final static long KEY_EVENT_MASK = 0x08;

    /**

     * The event mask for selecting mouse events.

     */

    public final static long MOUSE_EVENT_MASK = 0x10;

    /**

     * The event mask for selecting mouse motion events.

     */

    public final static long MOUSE_MOTION_EVENT_MASK = 0x20;

    /**

     * The event mask for selecting window events.

     */

    public final static long WINDOW_EVENT_MASK = 0x40;

    /**

     * The event mask for selecting action events.

     */

    public final static long ACTION_EVENT_MASK = 0x80;

    /**

     * The event mask for selecting adjustment events.

     */

    public final static long ADJUSTMENT_EVENT_MASK = 0x100;

    /**

     * The event mask for selecting item events.

     */

    public final static long ITEM_EVENT_MASK = 0x200;

    /**

     * The event mask for selecting text events.

     */

    public final static long TEXT_EVENT_MASK = 0x400;

    /**

     * The event mask for selecting input method events.

     */

    public final static long INPUT_METHOD_EVENT_MASK = 0x800;

    /**

     * The pseudo event mask for enabling input methods.

     * We're using one bit in the eventMask so we don't need

     * a separate field inputMethodsEnabled.

     */

    final static long INPUT_METHODS_ENABLED_MASK = 0x1000;

    /**

     * The event mask for selecting paint events.

     */

    public final static long PAINT_EVENT_MASK = 0x2000;

    /**

     * The event mask for selecting invocation events.

     */

    public final static long INVOCATION_EVENT_MASK = 0x4000;

    /**

     * The event mask for selecting hierarchy events.

     */

    public final static long HIERARCHY_EVENT_MASK = 0x8000;

    /**

     * The event mask for selecting hierarchy bounds events.

     */

    public final static long HIERARCHY_BOUNDS_EVENT_MASK = 0x10000;

    /**

     * The event mask for selecting mouse wheel events.

     * @since 1.4

     */

    public final static long MOUSE_WHEEL_EVENT_MASK = 0x20000;

    /**

     * The event mask for selecting window state events.

     * @since 1.4

     */

    public final static long WINDOW_STATE_EVENT_MASK = 0x40000;

    /**

     * The event mask for selecting window focus events.

     * @since 1.4

     */

    public final static long WINDOW_FOCUS_EVENT_MASK = 0x80000;

    /**

     * WARNING: there are more mask defined privately.  See

     * SunToolkit.GRAB_EVENT_MASK.

     */

    /**

     * The maximum value for reserved AWT event IDs. Programs defining

     * their own event IDs should use IDs greater than this value.

     */

    public final static int RESERVED_ID_MAX = 1999;

    // security stuff

    private static Field inputEvent_CanAccessSystemClipboard_Field = null;

    /*

     * JDK 1.1 serialVersionUID

     */

    private static final long serialVersionUID = -1825314779160409405L;

    static {

        /* ensure that the necessary native libraries are loaded */

        Toolkit.loadLibraries();

        if (!GraphicsEnvironment.isHeadless()) {

            initIDs();

        }

        AWTAccessor.setAWTEventAccessor(

            new AWTAccessor.AWTEventAccessor() {

                public void setPosted(AWTEvent ev) {

                    ev.isPosted = true;

                }

            });

    }

    private static synchronized Field get_InputEvent_CanAccessSystemClipboard() {

        if (inputEvent_CanAccessSystemClipboard_Field == null) {

            inputEvent_CanAccessSystemClipboard_Field =

                (Field)java.security.AccessController.doPrivileged(

                    new java.security.PrivilegedAction() {

                            public Object run() {

                                Field field = null;

                                try {

                                    field = InputEvent.class.

                                        getDeclaredField("canAccessSystemClipboard");

                                    field.setAccessible(true);

                                    return field;

                                } catch (SecurityException e) {

                                    }

                                } catch (NoSuchFieldException e) {

                                    }

                                }

                                return null;

                            }

                        });

        }

        return inputEvent_CanAccessSystemClipboard_Field;

    }

    /**

     * Initialize JNI field and method IDs for fields that may be

     * accessed from C.

     */

    private static native void initIDs();

    /**

     * Constructs an AWTEvent object from the parameters of a 1.0-style event.

     * @param event the old-style event

     */

    public AWTEvent(Event event) {

        this(event.target, event.id);

    }

    /**

     * Constructs an AWTEvent object with the specified source object and type.

     *

     * @param source the object where the event originated

     * @param id the event type

     */

    public AWTEvent(Object source, int id) {

        super(source);

        this.id = id;

        switch(id) {

          case ActionEvent.ACTION_PERFORMED:

          case ItemEvent.ITEM_STATE_CHANGED:

          case AdjustmentEvent.ADJUSTMENT_VALUE_CHANGED:

          case TextEvent.TEXT_VALUE_CHANGED:

            consumed = true;

            break;

          default:

        }

    }

    /**

     * Retargets an event to a new source. This method is typically used to

     * retarget an event to a lightweight child Component of the original

     * heavyweight source.

     * <p>

     * This method is intended to be used only by event targeting subsystems,

     * such as client-defined KeyboardFocusManagers. It is not for general

     * client use.

     *

     * @param newSource the new Object to which the event should be dispatched

     * @since 1.4

     */

    public void setSource(Object newSource) {

        if (source == newSource) {

            return;

        }

        Component comp = null;

        if (newSource instanceof Component) {

            comp = (Component)newSource;

            while (comp != null && comp.peer != null &&

                   (comp.peer instanceof LightweightPeer)) {

                comp = comp.parent;

            }

        }

        synchronized (this) {

            source = newSource;

            if (comp != null) {

                ComponentPeer peer = comp.peer;

                if (peer != null) {

                    nativeSetSource(peer);

                }

            }

        }

    }

    private native void nativeSetSource(ComponentPeer peer);

    /**

     * Returns the event type.

     */

    public int getID() {

        return id;

    }

    /**

     * Returns a String representation of this object.

     */

    public String toString() {

        String srcName = null;

        if (source instanceof Component) {

            srcName = ((Component)source).getName();

        } else if (source instanceof MenuComponent) {

            srcName = ((MenuComponent)source).getName();

        }

        return getClass().getName() + "[" + paramString() + "] on " +

            (srcName != null? srcName : source);

    }

    /**

     * Returns a string representing the state of this <code>Event</code>.

     * This method is intended to be used only for debugging purposes, and the

     * content and format of the returned string may vary between

     * implementations. The returned string may be empty but may not be

     * <code>null</code>.

     *

     * @return  a string representation of this event

     */

    public String paramString() {

        return "";

    }

    /**

     * Consumes this event, if this event can be consumed. Only low-level,

     * system events can be consumed

     */

    protected void consume() {

        switch(id) {

          case KeyEvent.KEY_PRESSED:

          case KeyEvent.KEY_RELEASED:

          case MouseEvent.MOUSE_PRESSED:

          case MouseEvent.MOUSE_RELEASED:

          case MouseEvent.MOUSE_MOVED:

          case MouseEvent.MOUSE_DRAGGED:

          case MouseEvent.MOUSE_ENTERED:

          case MouseEvent.MOUSE_EXITED:

          case MouseEvent.MOUSE_WHEEL:

          case InputMethodEvent.INPUT_METHOD_TEXT_CHANGED:

          case InputMethodEvent.CARET_POSITION_CHANGED:

              consumed = true;

              break;

          default:

              // event type cannot be consumed

        }

    }

    /**

     * Returns whether this event has been consumed.

     */

    protected boolean isConsumed() {

        return consumed;

    }

    /**

     * Converts a new event to an old one (used for compatibility).

     * If the new event cannot be converted (because no old equivalent

     * exists) then this returns null.

     *

     * Note: this method is here instead of in each individual new

     * event class in java.awt.event because we don't want to make

     * it public and it needs to be called from java.awt.

     */

    Event convertToOld() {

        Object src = getSource();

        int newid = id;

        switch(id) {

          case KeyEvent.KEY_PRESSED:

          case KeyEvent.KEY_RELEASED:

              KeyEvent ke = (KeyEvent)this;

              if (ke.isActionKey()) {

                  newid = (id == KeyEvent.KEY_PRESSED?

                           Event.KEY_ACTION : Event.KEY_ACTION_RELEASE);

              }

              int keyCode = ke.getKeyCode();

              if (keyCode == KeyEvent.VK_SHIFT ||

                  keyCode == KeyEvent.VK_CONTROL ||

                  keyCode == KeyEvent.VK_ALT) {

                  return null;  // suppress modifier keys in old event model.

              }

              // no mask for button1 existed in old Event - strip it out

              return new Event(src, ke.getWhen(), newid, 0, 0,

                               Event.getOldEventKey(ke),

                               (ke.getModifiers() & ~InputEvent.BUTTON1_MASK));

          case MouseEvent.MOUSE_PRESSED:

          case MouseEvent.MOUSE_RELEASED:

          case MouseEvent.MOUSE_MOVED:

          case MouseEvent.MOUSE_DRAGGED:

          case MouseEvent.MOUSE_ENTERED:

          case MouseEvent.MOUSE_EXITED:

              MouseEvent me = (MouseEvent)this;

              // no mask for button1 existed in old Event - strip it out

              Event olde = new Event(src, me.getWhen(), newid,

                               me.getX(), me.getY(), 0,

                               (me.getModifiers() & ~InputEvent.BUTTON1_MASK));

              olde.clickCount = me.getClickCount();

              return olde;

          case FocusEvent.FOCUS_GAINED:

              return new Event(src, Event.GOT_FOCUS, null);

          case FocusEvent.FOCUS_LOST:

              return new Event(src, Event.LOST_FOCUS, null);

          case WindowEvent.WINDOW_CLOSING:

          case WindowEvent.WINDOW_ICONIFIED:

          case WindowEvent.WINDOW_DEICONIFIED:

              return new Event(src, newid, null);

          case ComponentEvent.COMPONENT_MOVED:

              if (src instanceof Frame || src instanceof Dialog) {

                  Point p = ((Component)src).getLocation();

                  return new Event(src, 0, Event.WINDOW_MOVED, p.x, p.y, 0, 0);

              }

              break;

          case ActionEvent.ACTION_PERFORMED:

              ActionEvent ae = (ActionEvent)this;

              String cmd;

              if (src instanceof Button) {

                  cmd = ((Button)src).getLabel();

              } else if (src instanceof MenuItem) {

                  cmd = ((MenuItem)src).getLabel();

              } else {

                  cmd = ae.getActionCommand();

              }

              return new Event(src, 0, newid, 0, 0, 0, ae.getModifiers(), cmd);

          case ItemEvent.ITEM_STATE_CHANGED:

              ItemEvent ie = (ItemEvent)this;

              Object arg;

              if (src instanceof List) {

                  newid = (ie.getStateChange() == ItemEvent.SELECTED?

                           Event.LIST_SELECT : Event.LIST_DESELECT);

                  arg = ie.getItem();

              } else {

                  newid = Event.ACTION_EVENT;

                  if (src instanceof Choice) {

                      arg = ie.getItem();

                  } else { // Checkbox

                      arg = Boolean.valueOf(ie.getStateChange() == ItemEvent.SELECTED);

                  }

              }

              return new Event(src, newid, arg);

          case AdjustmentEvent.ADJUSTMENT_VALUE_CHANGED:

              AdjustmentEvent aje = (AdjustmentEvent)this;

              switch(aje.getAdjustmentType()) {

                case AdjustmentEvent.UNIT_INCREMENT:

                  newid = Event.SCROLL_LINE_DOWN;

                  break;

                case AdjustmentEvent.UNIT_DECREMENT:

                  newid = Event.SCROLL_LINE_UP;

                  break;

                case AdjustmentEvent.BLOCK_INCREMENT:

                  newid = Event.SCROLL_PAGE_DOWN;

                  break;

                case AdjustmentEvent.BLOCK_DECREMENT:

                  newid = Event.SCROLL_PAGE_UP;

                  break;

                case AdjustmentEvent.TRACK:

                  if (aje.getValueIsAdjusting()) {

                      newid = Event.SCROLL_ABSOLUTE;

                  }

                  else {

                      newid = Event.SCROLL_END;

                  }

                  break;

                default:

                  return null;

              }