Merged gcj-eclipse branch to trunk.

From-SVN: r120621

1 files changed, 199 insertions, 185 deletions

diff --git a/libjava/classpath/java/awt/LightweightDispatcher.java b/libjava/classpath/java/awt/LightweightDispatcher.java
index 3ea3f90..04196bd 100644
--- a/libjava/classpath/java/awt/LightweightDispatcher.java
+++ b/libjava/classpath/java/awt/LightweightDispatcher.java
@@ -38,7 +38,10 @@ exception statement from your version. */
 
 package java.awt;
 
+import java.awt.event.InputEvent;
 import java.awt.event.MouseEvent;
+import java.awt.event.MouseWheelEvent;
+import java.awt.peer.LightweightPeer;
 import java.util.WeakHashMap;
 
 /**
@@ -49,7 +52,7 @@ import java.util.WeakHashMap;
  *
  * @author Roman Kennke (kennke@aicas.com)
  */
-class LightweightDispatcher
+final class LightweightDispatcher
 {
 
   /**
@@ -60,26 +63,17 @@ class LightweightDispatcher
   private static WeakHashMap instances = new WeakHashMap();
 
   /**
-   * The component that is the start of a mouse dragging. All MOUSE_DRAGGED
-   * events that follow the initial press must have the source set to this,
-   * as well as the MOUSE_RELEASED event following the dragging.
-   */
-  private Component dragTarget;
-  
-  /**
-   * Stores the button number which started the drag operation. This is needed
-   * because we want to handle only one drag operation and only the button that
-   * started the dragging should be able to stop it (by a button release).
-   */
-  private int dragButton;
-
-  /**
    * The last mouse event target. If the target changes, additional
    * MOUSE_ENTERED and MOUSE_EXITED events must be dispatched.
    */
   private Component lastTarget;
 
   /**
+   * The current mouseEventTarget.
+   */
+  private Component mouseEventTarget;
+
+  /**
    * Returns an instance of LightweightDispatcher for the current thread's
    * thread group.
    *
@@ -113,9 +107,9 @@ class LightweightDispatcher
    *
    * @param event the event
    */
-  public boolean dispatchEvent(AWTEvent event)
+  public boolean dispatchEvent(final AWTEvent event)
   {
-    if (event instanceof MouseEvent && event.getSource() instanceof Window)
+    if (event instanceof MouseEvent)
       {
         MouseEvent mouseEvent = (MouseEvent) event;
         return handleMouseEvent(mouseEvent);
@@ -130,151 +124,49 @@ class LightweightDispatcher
    * @param ev the mouse event
    * @return whether or not we found a lightweight that handled the event.
    */
-  private boolean handleMouseEvent(MouseEvent ev)
+  private boolean handleMouseEvent(final MouseEvent ev)
   {
-    Window window = (Window) ev.getSource();
-    // Find the target for the mouse event. We first seach the deepest
-    // component at the specified location. The we go up to its parent and
-    // try to find a neighbor of the deepest component that is suitable as
-    // mouse event target (it must be showing, at that location and have either
-    // a MouseListener or MouseMotionListener installed). If no such component
-    // is found, then we walk up the container hierarchy and find the next
-    // container that has a MouseListener or MouseMotionListener installed.
-    Component deepest = window.findComponentAt(ev.getX(), ev.getY());
-    if (deepest == null)
-      return false;
-    Container parent = deepest.getParent();
-    Point loc = ev.getPoint();
-    loc = convertPointToChild(window, loc, parent);
-    Component target = null;
-    if (parent != null)
-      {
-        target = findTarget(parent, loc);
-        while (target == null && parent != null)
-          {
-            if (parent.mouseListener != null
-                || parent.mouseMotionListener != null
-                || (parent.eventMask
-                    & (AWTEvent.MOUSE_EVENT_MASK
-                        | AWTEvent.MOUSE_MOTION_EVENT_MASK)) != 0)
-              {
-                target = parent;
-              }
-            else
-              parent = parent.getParent();
-          }
-      }
-    if (target == null || target.isLightweight())
+    Container container = (Container) ev.getSource();
+    Component target = findTarget(container, ev.getX(), ev.getY());
+    trackEnterExit(target, ev);
+    int id = ev.getID();
+
+    // Dont update the mouseEventTarget when dragging. Also, MOUSE_CLICKED
+    // must be dispatched to the original target of MOUSE_PRESSED, so don't
+    // update in this case either.
+    if (! isDragging(ev) && id != MouseEvent.MOUSE_CLICKED)
+      mouseEventTarget = (target != container) ? target : null;
+
+    if (mouseEventTarget != null)
       {
-        // Dispatch additional MOUSE_EXITED and MOUSE_ENTERED if event target
-        // is different from the last event target.
-        if (target != lastTarget)
+        switch (id)
           {
-            if (lastTarget != null)
-              {
-                Point p1 = convertPointToChild(window, ev.getPoint(),
-                                               lastTarget);
-                MouseEvent mouseExited =
-                  new MouseEvent(lastTarget, MouseEvent.MOUSE_EXITED,
-                                 ev.getWhen(), ev.getModifiers(), p1.x, p1.y,
-                                 ev.getClickCount(), ev.isPopupTrigger());
-                //System.err.println("event: " + mouseExited);
-                lastTarget.dispatchEvent(mouseExited);
-              }
-            
-            // If a target exists dispatch the MOUSE_ENTERED event.
-            // Experimenting shows that the MOUSE_ENTERED is also dispatched
-            // when the mouse is dragging.
-            if (target != null)
-              {
-                Point p = convertPointToChild(window, ev.getPoint(), target);
-                MouseEvent mouseEntered =
-                  new MouseEvent(target,
-                                 MouseEvent.MOUSE_ENTERED, ev.getWhen(),
-                                 ev.getModifiers(), p.x, p.y, ev.getClickCount(),
-                                 ev.isPopupTrigger());
-                //System.err.println("event: " + mouseEntered);
-                target.dispatchEvent(mouseEntered);
-              }
-          }
-        
-        switch (ev.getID())
-        {
-          case MouseEvent.MOUSE_PRESSED:
-            // Handle the start of a drag operation or discard the event if
-            // one is already in progress. This prevents focus changes with the
-            // other mouse buttons when one is used for dragging.
-            if (dragTarget == null)
-              {
-                lastTarget = dragTarget = target;
-                
-                // Save the button that started the drag operation.
-                dragButton = ev.getButton();
-              }
-            else
-              return false;
-            
+          case MouseEvent.MOUSE_ENTERED:
+          case MouseEvent.MOUSE_EXITED:
+            // This is already handled in trackEnterExit().
             break;
+          case MouseEvent.MOUSE_PRESSED:
           case MouseEvent.MOUSE_RELEASED:
-            // Stop the drag operation only when the button that started
-            // it was released.
-            if (dragTarget != null && dragButton == ev.getButton())
-              {
-                // Only post MOUSE_RELEASED to dragTarget (set in
-                // MOUSE_PRESSED) when the dragTarget is actually visible.
-                // Otherwise post the event to the normal target.
-                if (dragTarget.isVisible())
-                  target = dragTarget;
-                dragTarget = null;
-              }
-            
-            lastTarget = target;
+          case MouseEvent.MOUSE_MOVED:
+            redispatch(ev, mouseEventTarget, id);
             break;
           case MouseEvent.MOUSE_CLICKED:
-            // When we receive a MOUSE_CLICKED, we set the target to the
-            // previous target, which must have been a MOUSE_RELEASED event.
-            // This is necessary for the case when the MOUSE_RELEASED has
-            // caused the original target (like an internal component) go
-            // away.
-            // This line is the reason why it is not possible to move the
-            // 'lastTarget = target' assignment before the switch-statement.
-            target = lastTarget;
+            // MOUSE_CLICKED must be dispatched to the original target of
+            // MOUSE_PRESSED.
+            if (target == mouseEventTarget)
+              redispatch(ev, mouseEventTarget, id);
             break;
           case MouseEvent.MOUSE_DRAGGED:
-            // We consider only dragTarget for redispatching the event still
-            // we have to act in a way that the newly found target component
-            // was handled.
-            lastTarget = target;
-            target = dragTarget;
+            if (isDragging(ev))
+              redispatch(ev, mouseEventTarget, id);
             break;
-          default:
-            // Only declare current target as the old value in all other
-            // cases.
-            lastTarget = target;
-            break;
-        }
-
-        if (target != null)
-          {
-            Point targetCoordinates = convertPointToChild(window,
-                                                          ev.getPoint(),
-                                                          target);
-            int dx = targetCoordinates.x - ev.getX();
-            int dy = targetCoordinates.y - ev.getY();
-            ev.translatePoint(dx, dy);
-            ev.setSource(target);
-            target.dispatchEvent(ev);
-            
-            // We reset the event, so that the normal event dispatching is not
-            // influenced by this modified event.
-            ev.setSource(window);
-            ev.translatePoint(-dx, -dy);
+          case MouseEvent.MOUSE_WHEEL:
+            redispatch(ev, mouseEventTarget, id);
           }
-
-	return true;
+        ev.consume();
       }
-    else
-      return false;
+
+    return ev.isConsumed();
   }
 
   /**
@@ -290,58 +182,180 @@ class LightweightDispatcher
    * @return the actual receiver of the mouse event, or null, if no such
    *         component has been found
    */
-  private Component findTarget(Container c, Point loc)
+  private Component findTarget(final Container c, final int x, final int y)
   {
-    int numComponents = c.getComponentCount();
     Component target = null;
-    if (c != null)
+
+    // First we check the children of the container.
+
+    // Note: It is important that we use the package private Container
+    // fields ncomponents and component here. There are applications
+    // that override getComponentCount()
+    // and getComponent() to hide internal components, which makes
+    // the LightweightDispatcher not work correctly in these cases.
+    // As a positive sideeffect this is slightly more efficient.
+    int nChildren = c.ncomponents;
+    for (int i = 0; i < nChildren && target == null; i++)
       {
-        for (int i = 0; i < numComponents; i++)
+        Component child = c.component[i];
+        int childX = x - child.x;
+        int childY = y - child.y;
+        if (child != null && child.visible
+            && child.peer instanceof LightweightPeer
+            && child.contains(childX, childY))
           {
-            Component child = c.getComponent(i);
-            if (child.isShowing())
+            // Check if there's a deeper possible target.
+            if (child instanceof Container)
               {
-                if (child.contains(loc.x - child.getX(), loc.y - child.getY())
-                    && (child.mouseListener != null 
-                        || child.mouseMotionListener != null
-                        || (child.eventMask
-                            & (AWTEvent.MOUSE_EVENT_MASK
-                                | AWTEvent.MOUSE_MOTION_EVENT_MASK)) != 0))
-                  {
-                    target = child;
-                    break;
-                  }
+                Component deeper = findTarget((Container) child,
+                                              childX, childY);
+                if (deeper != null)
+                  target = deeper;
               }
+            // Check if the child itself is interested in mouse events.
+            else if (isMouseListening(child))
+              target = child;
           }
       }
+
+    // Check the container itself, if we didn't find a target yet.
+    if (target == null  && c.contains(x, y) && isMouseListening(c))
+      target = c;
+
     return target;
   }
 
   /**
-   * Converts a point in the parent's coordinate system to a child coordinate
-   * system. The resulting point is stored in the same Point object and
-   * returned.
+   * Checks if the specified component would be interested in a mouse event.
+   *
+   * @param c the component to check
+   *
+   * @return <code>true</code> if the component has mouse listeners installed,
+   *         <code>false</code> otherwise
+   */
+  private boolean isMouseListening(final Component c)
+  {
+    // Note: It is important to NOT check if the component is listening
+    // for a specific event (for instance, mouse motion events). The event
+    // gets dispatched to the component if the component is listening
+    // for ANY mouse event, even when the component is not listening for the
+    // specific type of event. There are applications that depend on this
+    // (sadly).
+    return c.mouseListener != null
+           || c.mouseMotionListener != null
+           || c.mouseWheelListener != null
+           || (c.eventMask & AWTEvent.MOUSE_EVENT_MASK) != 0
+           || (c.eventMask & AWTEvent.MOUSE_MOTION_EVENT_MASK) != 0
+           || (c.eventMask & AWTEvent.MOUSE_WHEEL_EVENT_MASK) != 0;
+  }
+
+  /**
+   * Tracks MOUSE_ENTERED and MOUSE_EXIT as well as MOUSE_MOVED and
+   * MOUSE_DRAGGED and creates synthetic MOUSE_ENTERED and MOUSE_EXITED for
+   * lightweight component.s
+   *
+   * @param target the current mouse event target
+   * @param ev the mouse event
+   */
+  private void trackEnterExit(final Component target, final MouseEvent ev)
+  {
+    int id = ev.getID();
+    if (target != lastTarget)
+      {
+        if (lastTarget != null)
+          redispatch(ev, lastTarget, MouseEvent.MOUSE_EXITED);
+        if (id == MouseEvent.MOUSE_EXITED)
+          ev.consume();
+        if (target != null)
+          redispatch(ev, target, MouseEvent.MOUSE_ENTERED);
+        if (id == MouseEvent.MOUSE_ENTERED)
+          ev.consume();
+        lastTarget = target;
+      }
+
+  }
+
+  /**
+   * Redispatches the specified mouse event to the specified target with the
+   * specified id.
    *
-   * @param parent the parent component
-   * @param p the point
-   * @param child the child component
+   * @param ev the mouse event
+   * @param target the new target
+   * @param id the new id
+   */
+  private void redispatch(MouseEvent ev, Component target, int id)
+  {
+    Component source = ev.getComponent();
+    if (target != null)
+      {
+        // Translate coordinates.
+        int x = ev.getX();
+        int y = ev.getY();
+        for (Component c = target; c != null && c != source; c = c.getParent())
+          {
+            x -= c.x;
+            y -= c.y;
+          }
+
+        // Retarget event.
+        MouseEvent retargeted;
+        if (id == MouseEvent.MOUSE_WHEEL)
+          {
+            MouseWheelEvent mwe = (MouseWheelEvent) ev;
+            retargeted = new MouseWheelEvent(target, id, ev.getWhen(),
+                                             ev.getModifiers()
+                                             | ev.getModifiersEx(), x, y,
+                                             ev.getClickCount(),
+                                             ev.isPopupTrigger(),
+                                             mwe.getScrollType(),
+                                             mwe.getScrollAmount(),
+                                             mwe.getWheelRotation());
+          }
+        else
+          {
+            retargeted = new MouseEvent(target, id, ev.getWhen(),
+                                       ev.getModifiers() | ev.getModifiersEx(),
+                                       x, y, ev.getClickCount(),
+                                       ev.isPopupTrigger(), ev.getButton());
+          }
+
+        if (target == source)
+          ((Container) target).dispatchNoLightweight(retargeted);
+        else
+          target.dispatchEvent(retargeted);
+      }
+  }
+
+  /**
+   * Determines if we are in the middle of a drag operation, that is, if
+   * any of the buttons is held down.
+   *
+   * @param ev the mouse event to check
    *
-   * @return the translated point
+   * @return <code>true</code> if we are in the middle of a drag operation,
+   *         <code>false</code> otherwise
    */
-  private Point convertPointToChild(Component parent, Point p,
-                                   Component child)
+  private boolean isDragging(MouseEvent ev)
   {
-    int offX = 0;
-    int offY = 0;
-    Component comp = child;
-    while (comp != null && comp != parent)
+    int mods = ev.getModifiersEx();
+    int id = ev.getID();
+    if (id == MouseEvent.MOUSE_PRESSED || id == MouseEvent.MOUSE_RELEASED)
       {
-        offX += comp.getX();
-        offY += comp.getY();
-        comp = comp.getParent();
+        switch (ev.getButton())
+          {
+            case MouseEvent.BUTTON1:
+              mods ^= InputEvent.BUTTON1_DOWN_MASK;
+              break;
+            case MouseEvent.BUTTON2:
+              mods ^= InputEvent.BUTTON2_DOWN_MASK;
+              break;
+            case MouseEvent.BUTTON3:
+              mods ^= InputEvent.BUTTON3_DOWN_MASK;
+              break;
+          }
       }
-    p.x -= offX;
-    p.y -= offY;
-    return p;
+    return (mods & (InputEvent.BUTTON1_DOWN_MASK
+                    | InputEvent.BUTTON2_DOWN_MASK
+                    | InputEvent.BUTTON3_DOWN_MASK)) != 0;
   }
 }