### Eclipse Workspace Patch 1.0
#P org.eclipse.jdt.core
Index: model/org/eclipse/jdt/internal/core/BufferManager.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/BufferManager.java,v
retrieving revision 1.27
diff -u -r1.27 BufferManager.java
--- model/org/eclipse/jdt/internal/core/BufferManager.java	6 Mar 2007 02:38:49 -0000	1.27
+++ model/org/eclipse/jdt/internal/core/BufferManager.java	9 May 2007 15:34:57 -0000
@@ -72,6 +72,15 @@
 			owner, 
 			element.isReadOnly());
 }
+public static IBuffer createNullBuffer(IOpenable owner) {
+	IJavaElement element = (IJavaElement)owner;
+	IResource resource = element.getResource();
+	return 
+		new NullBuffer(
+			resource instanceof IFile ? (IFile)resource : null, 
+			owner, 
+			element.isReadOnly());
+}
 /**
  * Returns the open buffer associated with the given owner,
  * or <code>null</code> if the owner does not have an open
Index: model/org/eclipse/jdt/internal/core/Openable.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/Openable.java,v
retrieving revision 1.111
diff -u -r1.111 Openable.java
--- model/org/eclipse/jdt/internal/core/Openable.java	29 Mar 2006 03:08:47 -0000	1.111
+++ model/org/eclipse/jdt/internal/core/Openable.java	9 May 2007 15:34:57 -0000
@@ -258,6 +258,9 @@
 			// try to (re)open a buffer
 			buffer = openBuffer(null, info);
 		}
+		if (buffer instanceof NullBuffer) {
+			return null;
+		}
 		return buffer;
 	} else {
 		return null;
Index: model/org/eclipse/jdt/internal/core/ClassFile.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/ClassFile.java,v
retrieving revision 1.134
diff -u -r1.134 ClassFile.java
--- model/org/eclipse/jdt/internal/core/ClassFile.java	6 Mar 2007 02:38:49 -0000	1.134
+++ model/org/eclipse/jdt/internal/core/ClassFile.java	9 May 2007 15:34:57 -0000
@@ -354,7 +354,7 @@
 		// .class file not on classpath, create a new buffer to be nice (see https://bugs.eclipse.org/bugs/show_bug.cgi?id=41444)
 		Object info = ((ClassFile) getClassFile()).getBinaryTypeInfo((IFile) getResource());
 		IBuffer buffer = openBuffer(null, info);
-		if (buffer != null)
+		if (buffer != null && !(buffer instanceof NullBuffer))
 			return buffer;
 		if (status.getCode() == IJavaModelStatusConstants.ELEMENT_NOT_ON_CLASSPATH)
 			return null; // don't throw a JavaModelException to be able to open .class file outside the classpath (see https://bugs.eclipse.org/bugs/show_bug.cgi?id=138507)
@@ -633,21 +633,30 @@
 		if (buffer == null) return null;
 		BufferManager bufManager = getBufferManager();
 		bufManager.addBuffer(buffer);
-		
+
 		// set the buffer source
 		if (buffer.getCharacters() == null){
 			buffer.setContents(contents);
 		}
-		
+
 		// listen to buffer changes
-		buffer.addBufferChangedListener(this);	
-				
+		buffer.addBufferChangedListener(this);
+
 		// do the source mapping
 		mapper.mapSource(getType(), contents, info);
-		
+
+		return buffer;
+	} else {
+		// create buffer
+		IBuffer buffer = BufferManager.createNullBuffer(this);
+		if (buffer == null) return null;
+		BufferManager bufManager = getBufferManager();
+		bufManager.addBuffer(buffer);
+
+		// listen to buffer changes
+		buffer.addBufferChangedListener(this);
 		return buffer;
 	}
-	return null;
 }
 /* package */ static String simpleName(char[] className) {
 	if (className == null)
Index: model/org/eclipse/jdt/internal/core/NullBuffer.java
===================================================================
RCS file: model/org/eclipse/jdt/internal/core/NullBuffer.java
diff -N model/org/eclipse/jdt/internal/core/NullBuffer.java
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ model/org/eclipse/jdt/internal/core/NullBuffer.java	1 Jan 1970 00:00:00 -0000
@@ -0,0 +1,28 @@
+/*******************************************************************************
+ * Copyright (c) 2007 IBM Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     IBM Corporation - initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.jdt.internal.core;
+
+import org.eclipse.core.resources.IFile;
+import org.eclipse.jdt.core.IOpenable;
+
+/**
+ * @author othomann
+ *
+ */
+public class NullBuffer extends Buffer {
+	/**
+	 * Creates a new null buffer on an underlying resource.
+	 */
+	public NullBuffer(IFile file, IOpenable owner, boolean readOnly) {
+		super(file, owner, readOnly);
+	}
+}