Re: Patch: embedded window extension

[Michael Koch <konqueror at gmx dot de>]

Am Samstag, 17. Juli 2004 17:25 schrieb Eric Blake:
> This patch seems a little too simple for me.  By default,
> reflection is supposed to follow the same accessibility rules the
> compiler would follow, meaning that the reflection should throw an
> IllegalAccessException unless you call setAccessible() on peerField
> to change the default.  And calling setAccessible requires a
> security check, so you will have to set up a PrivelegedAction so
> that your call will always succeed.  Did you just expose a bug in
> the reflection implementation?

Hmm, I used jamvm. Perhaps its not the best candidate to test this 
code.

I wrote now the attached patch for this problem. Can you please review 
it ? It makes jamvm hang but I'm not sure where the problem is 
currently.


Michael

Index: gnu/java/awt/EmbeddedWindow.java
===================================================================
RCS file: /cvsroot/classpath/classpath/gnu/java/awt/EmbeddedWindow.java,v
retrieving revision 1.3
diff -u -b -B -r1.3 EmbeddedWindow.java
--- gnu/java/awt/EmbeddedWindow.java	17 Jul 2004 07:17:04 -0000	1.3
+++ gnu/java/awt/EmbeddedWindow.java	22 Jul 2004 09:03:37 -0000
@@ -45,6 +45,8 @@
 import java.awt.Frame;
 import java.awt.Toolkit;
 import java.lang.reflect.Field;
+import java.security.AccessController;
+import java.security.PrivilegedAction;
 
 /**
  * Represents an AWT window that can be embedded into another
@@ -88,14 +90,23 @@
 
     if (! (tk instanceof EmbeddedWindowSupport))
       throw new UnsupportedOperationException
-        ("Embedded windows are not supported by the current peers: " + tk.getClass());
+        ("Embedded windows are not supported by the current peers: "
+	 + tk.getClass());
+
+    final EmbeddedWindowSupport support = (EmbeddedWindowSupport) tk;
 
     // Circumvent the package-privateness of the AWT internal
     // java.awt.Component.peer member variable.
+    AccessController.doPrivileged(new PrivilegedAction()
+      {
+	public Object run()
+	{
     try
       {
 	Field peerField = Component.class.getDeclaredField("peer");
-	peerField.set(this, ((EmbeddedWindowSupport) tk).createEmbeddedWindow (this));
+	      peerField.setAccessible(true);
+	      peerField.set(EmbeddedWindow.this,
+			    support.createEmbeddedWindow(EmbeddedWindow.this));
       }
     catch (IllegalAccessException e)
       {
@@ -106,6 +117,10 @@
 	// This should never happen.
       }
 
+	  return null;
+        }
+      });
+
     super.addNotify();
   }