1 files changed, 61 insertions, 2 deletions
diff --git a/java/awt/Panel.java b/java/awt/Panel.java
index b84c0d0a6..dbe322896 100644
--- a/java/awt/Panel.java
+++ b/java/awt/Panel.java
@@ -38,6 +38,7 @@ exception statement from your version. */
 
 package java.awt;
 
+import java.awt.event.PaintEvent;
 import javax.accessibility.Accessible;
 import javax.accessibility.AccessibleContext;
 import javax.accessibility.AccessibleRole;
@@ -62,6 +63,19 @@ public class Panel extends Container implements Accessible
   /** The cached accessible context. */
   private transient AccessibleContext context;
 
+  /** Flag set when the first system-requested paint event is
+      dispatched. */
+  private transient boolean initialSystemUpdateDone;
+
+  /** Flag set when the first application-requested paint event is
+      consumed. */
+  private transient boolean initialUpdateConsumed;
+
+  /*
+   * The number used to generate the name returned by getName.
+   */
+  private static transient long next_panel_number = 0;
+
   /**
    * Initializes a new instance of <code>Panel</code> that has a default
    * layout manager of <code>FlowLayout</code>.
@@ -84,6 +98,36 @@ public class Panel extends Container implements Accessible
   }
 
   /**
+   * Consume initial application-requested paint event if it has not
+   * already been consumed, and if the initial system-requested paint
+   * event has not already been handled.  Otherwise, call
+   * super.dispatchEventImpl.  These extra steps are required to
+   * prevent a Panel from being painted twice when it is initially
+   * shown.
+   *
+   * @param e the event to dispatch
+   */
+  void dispatchEventImpl (AWTEvent e)
+  {
+    if (e instanceof PaintEvent)
+      {
+        if (e.id == PaintEvent.UPDATE)
+          {
+            if (!initialUpdateConsumed
+                && !initialSystemUpdateDone)
+              {
+                e.consume ();
+                initialUpdateConsumed = true;
+              }
+          }
+        else if (e.id == PaintEvent.PAINT)
+          initialSystemUpdateDone = true;
+      }
+    else
+      super.dispatchEventImpl (e);
+  }
+
+  /**
    * Notifies this object to create its native peer.
    *
    * @see #isDisplayable()
@@ -141,5 +185,20 @@ public class Panel extends Container implements Accessible
     {
       return AccessibleRole.PANEL;
     }
-  } // class AccessibleAWTPanel
-} // class Panel 
+  }
+
+  /**
+   * Generate a unique name for this panel.
+   *
+   * @return A unique name for this panel.
+   */
+  String generateName ()
+  {
+    return "panel" + getUniqueLong ();
+  }
+
+  private static synchronized long getUniqueLong ()
+  {
+    return next_panel_number++;
+  }
+}