### Eclipse Workspace Patch 1.0
#P org.eclipse.jdt.core
Index: model/org/eclipse/jdt/core/JavaCore.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/model/org/eclipse/jdt/core/JavaCore.java,v
retrieving revision 1.614
diff -u -r1.614 JavaCore.java
--- model/org/eclipse/jdt/core/JavaCore.java	28 Apr 2008 19:45:56 -0000	1.614
+++ model/org/eclipse/jdt/core/JavaCore.java	15 May 2008 13:16:12 -0000
@@ -2335,13 +2335,13 @@
 	 * Returns the Java model element corresponding to the given handle identifier
 	 * generated by <code>IJavaElement.getHandleIdentifier()</code>, or
 	 * <code>null</code> if unable to create the associated element.
-	 * If the returned Java element is an <code>ICompilationUnit</code>, its owner
-	 * is the given owner if such a working copy exists, otherwise the compilation unit
-	 * is a primary compilation unit.
+	 * If the returned Java element is an <code>ICompilationUnit</code> or an element
+	 * inside a compilation unit, the compilation unit's owner is the given owner if such a 
+	 * working copy exists, otherwise the compilation unit is a primary compilation unit.
 	 *
 	 * @param handleIdentifier the given handle identifier
 	 * @param owner the owner of the returned compilation unit, ignored if the returned
-	 *   element is not a compilation unit
+	 *   element is not a compilation unit, or an element inside a compilation unit
 	 * @return the Java element corresponding to the handle identifier
 	 * @since 3.0
 	 */
@@ -2349,6 +2349,8 @@
 		if (handleIdentifier == null) {
 			return null;
 		}
+		if (owner == null)
+			owner = DefaultWorkingCopyOwner.PRIMARY;
 		MementoTokenizer memento = new MementoTokenizer(handleIdentifier);
 		JavaModel model = JavaModelManager.getJavaModelManager().getJavaModel();
 		return model.getHandleFromMemento(memento, owner);
#P org.eclipse.jdt.core.tests.model
Index: src/org/eclipse/jdt/core/tests/model/MementoTests.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/MementoTests.java,v
retrieving revision 1.22
diff -u -r1.22 MementoTests.java
--- src/org/eclipse/jdt/core/tests/model/MementoTests.java	24 Oct 2007 13:50:40 -0000	1.22
+++ src/org/eclipse/jdt/core/tests/model/MementoTests.java	15 May 2008 13:16:14 -0000
@@ -267,7 +267,7 @@
 /**
  * Tests that a compilation unit can be persisted and restored using its memento.
  */
-public void testCompilationUnitMemento() {
+public void testCompilationUnitMemento1() {
 	ICompilationUnit cu = getCompilationUnit("/P/src/p/X.java");
 	assertMemento(
 		"=P/src<p{X.java",
@@ -278,6 +278,17 @@
 		"=P/src<{Y.java",
 		cu);
 }
+/*
+ * Ensure that restoring a compilation unit memento with a null owner doesn't create an
+ * invalid handle
+ * (regression test for https://bugs.eclipse.org/bugs/show_bug.cgi?id=205917 )
+ */
+public void testCompilationUnitMemento2() throws Exception {
+	ICompilationUnit cu = getCompilationUnit("/P/src/p/X.java");
+	String handleIdentifier = cu.getHandleIdentifier();
+	cu = (ICompilationUnit) JavaCore.create(handleIdentifier, null);
+	assertEquals(cu, cu); // should not throw an NPE
+}
 /**
  * Tests that a binary field in an external jar can be persisted and restored using its memento.
  */