### Eclipse Workspace Patch 1.0
#P org.eclipse.jdt.core
Index: compiler/org/eclipse/jdt/internal/compiler/ast/TypeDeclaration.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/TypeDeclaration.java,v
retrieving revision 1.162
diff -u -r1.162 TypeDeclaration.java
--- compiler/org/eclipse/jdt/internal/compiler/ast/TypeDeclaration.java	25 Nov 2009 04:56:02 -0000	1.162
+++ compiler/org/eclipse/jdt/internal/compiler/ast/TypeDeclaration.java	17 May 2010 13:40:49 -0000
@@ -1187,6 +1187,28 @@
 			ReferenceBinding existingType = (ReferenceBinding) existing;
 			if (existingType instanceof TypeVariableBinding) {
 				blockScope.problemReporter().typeHiding(this, (TypeVariableBinding) existingType);
+				// https://bugs.eclipse.org/bugs/show_bug.cgi?id=312989, check for collision with enclosing type.
+				Scope outerScope = blockScope.parent;
+checkOuterScope:while (outerScope != null) {
+					Binding existing2 = outerScope.getType(this.name);
+					if (existing2 instanceof TypeVariableBinding && existing2.isValidBinding()) {
+						TypeVariableBinding tvb = (TypeVariableBinding) existingType;
+						Binding declaringElement = tvb.declaringElement;
+						if (declaringElement instanceof ReferenceBinding
+								&& CharOperation.equals(((ReferenceBinding) declaringElement).sourceName(), this.name)) {
+							blockScope.problemReporter().typeCollidesWithEnclosingType(this);
+							break checkOuterScope;
+						}
+					} else if (existing2 instanceof ReferenceBinding
+							&& existing2.isValidBinding()
+							&& outerScope.isDefinedInType((ReferenceBinding) existing2)) { 
+							blockScope.problemReporter().typeCollidesWithEnclosingType(this);
+							break checkOuterScope;
+					} else if (existing2 == null) {
+						break checkOuterScope;
+					}
+					outerScope = outerScope.parent;
+				}
 			} else if (existingType instanceof LocalTypeBinding
 						&& ((LocalTypeBinding) existingType).scope.methodScope() == blockScope.methodScope()) {
 					// dup in same method
#P org.eclipse.jdt.core.tests.compiler
Index: src/org/eclipse/jdt/core/tests/compiler/regression/InnerClass15Test.java
===================================================================
RCS file: src/org/eclipse/jdt/core/tests/compiler/regression/InnerClass15Test.java
diff -N src/org/eclipse/jdt/core/tests/compiler/regression/InnerClass15Test.java
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ src/org/eclipse/jdt/core/tests/compiler/regression/InnerClass15Test.java	1 Jan 1970 00:00:00 -0000
@@ -0,0 +1,142 @@
+/*******************************************************************************
+ * Copyright (c) 2010 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.core.tests.compiler.regression;
+
+import java.util.Map;
+
+import junit.framework.Test;
+
+import org.eclipse.jdt.internal.compiler.impl.CompilerOptions;
+
+public class InnerClass15Test extends AbstractRegressionTest {
+public InnerClass15Test(String name) {
+	super(name);
+}
+static {
+//	TESTS_NUMBERS = new int[] { 2 };
+}
+public static Test suite() {
+	return buildMinimalComplianceTestSuite(testClass(), F_1_5);
+}
+protected Map getCompilerOptions() {
+	Map options = super.getCompilerOptions();
+	options.put(CompilerOptions.OPTION_ReportRawTypeReference, CompilerOptions.IGNORE);
+	return options;
+}
+public void test001() {
+	this.runNegativeTest(new String[] {
+		"X.java",
+		"class X {\n" + 
+		"	<X> void foo() {\n" + 
+		"		class X {}\n" + 
+		"	}\n" + 
+		"}",
+	},
+	"----------\n" + 
+	"1. WARNING in X.java (at line 2)\n" + 
+	"	<X> void foo() {\n" + 
+	"	 ^\n" + 
+	"The type parameter X is hiding the type X\n" + 
+	"----------\n" + 
+	"2. WARNING in X.java (at line 3)\n" + 
+	"	class X {}\n" + 
+	"	      ^\n" + 
+	"The nested type X is hiding the type parameter X of the generic method foo() of type X\n" + 
+	"----------\n" + 
+	"3. ERROR in X.java (at line 3)\n" + 
+	"	class X {}\n" + 
+	"	      ^\n" + 
+	"The nested type X cannot hide an enclosing type\n" + 
+	"----------\n");
+}
+public void test002() {
+	this.runNegativeTest(new String[] {
+		"X.java",
+		"class X<X> {\n" + 
+		"	void foo() {\n" + 
+		"		class X {}\n" + 
+		"	}\n" + 
+		"}",
+	},
+	"----------\n" + 
+	"1. WARNING in X.java (at line 1)\n" + 
+	"	class X<X> {\n" + 
+	"	        ^\n" + 
+	"The type parameter X is hiding the type X<X>\n" + 
+	"----------\n" + 
+	"2. WARNING in X.java (at line 3)\n" + 
+	"	class X {}\n" + 
+	"	      ^\n" + 
+	"The nested type X is hiding the type parameter X of type X<X>\n" + 
+	"----------\n" + 
+	"3. ERROR in X.java (at line 3)\n" + 
+	"	class X {}\n" + 
+	"	      ^\n" + 
+	"The nested type X cannot hide an enclosing type\n" + 
+	"----------\n");
+}
+// https://bugs.eclipse.org/bugs/show_bug.cgi?id=312989
+// note javac reports an error for this test, but that is
+// incorrect, compare and contrast javac behavior with
+// test004.
+public void test003() {
+	this.runNegativeTest(new String[] {
+		"Y.java",
+		"class Y {\n" +
+		"class X {}\n" + 
+		"	<X> void foo() {\n" + 
+		"		class X {}\n" + 
+		"	}\n" + 
+		"}",
+	},
+	"----------\n" + 
+	"1. WARNING in Y.java (at line 3)\n" + 
+	"	<X> void foo() {\n" + 
+	"	 ^\n" + 
+	"The type parameter X is hiding the type Y.X\n" + 
+	"----------\n" + 
+	"2. WARNING in Y.java (at line 4)\n" + 
+	"	class X {}\n" + 
+	"	      ^\n" + 
+	"The nested type X is hiding the type parameter X of the generic method foo() of type Y\n" + 
+	"----------\n" + 
+	"3. WARNING in Y.java (at line 4)\n" + 
+	"	class X {}\n" + 
+	"	      ^\n" + 
+	"The type X is never used locally\n" + 
+	"----------\n");
+}
+public void test004() {
+	this.runNegativeTest(new String[] {
+		"Y.java",
+		"class Y {\n" +
+		"class X {}\n" + 
+		"   void foo() {\n" + 
+		"		class X {}\n" + 
+		"	}\n" + 
+		"}",
+	},
+	"----------\n" + 
+	"1. WARNING in Y.java (at line 4)\n" + 
+	"	class X {}\n" + 
+	"	      ^\n" + 
+	"The type X is hiding the type Y.X\n" + 
+	"----------\n" + 
+	"2. WARNING in Y.java (at line 4)\n" + 
+	"	class X {}\n" + 
+	"	      ^\n" + 
+	"The type X is never used locally\n" + 
+	"----------\n");
+}
+public static Class testClass() {
+	return InnerClass15Test.class;
+}
+}
Index: src/org/eclipse/jdt/core/tests/compiler/regression/TestAll.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/TestAll.java,v
retrieving revision 1.85
diff -u -r1.85 TestAll.java
--- src/org/eclipse/jdt/core/tests/compiler/regression/TestAll.java	11 May 2010 18:53:50 -0000	1.85
+++ src/org/eclipse/jdt/core/tests/compiler/regression/TestAll.java	17 May 2010 13:40:59 -0000
@@ -94,6 +94,7 @@
 	since_1_5.add(Deprecated15Test.class);
 	since_1_5.add(InnerEmulationTest_1_5.class);
 	since_1_5.add(AssignmentTest_1_5.class);
+	since_1_5.add(InnerClass15Test.class);
 
 	// Tests to run when compliance is greater than 1.5
 	ArrayList since_1_6 = new ArrayList();