7164256: EnumMap clone doesn't clear the entrySet keeping a reference to the original Map

Reviewed-by: alanb, chegar, forax, mduigou
Contributed-by: dbelfer@gmail.com

src/share/classes/java/util/EnumMap.java

@@ -730,6 +730,7 @@ public class EnumMap<K extends Enum<K>, V> extends AbstractMap<K, V>
             throw new AssertionError();
         }
         result.vals = result.vals.clone();
+        result.entrySet = null;
         return result;
     }
 

test/java/util/EnumMap/ProperEntrySetOnClone.java

+/*
+ * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug     7164256
+ * @summary EnumMap.entrySet() returns an entrySet referencing to the cloned instance
+ * @author  Diego Belfer
+ */
+
+import java.util.EnumMap;
+
+public class ProperEntrySetOnClone {
+    public enum Test {
+        ONE, TWO
+    }
+
+    public static void main(String[] args) {
+        EnumMap<Test, String> map1 = new EnumMap<Test, String>(Test.class);
+        map1.put(Test.ONE, "1");
+        map1.put(Test.TWO, "2");
+
+        // We need to force creation of the map1.entrySet
+        int size = map1.entrySet().size();
+        if (size != 2) {
+            throw new RuntimeException(
+                    "Invalid size in original map. Expected: 2 was: " + size);
+        }
+
+        EnumMap<Test, String> map2 = map1.clone();
+        map2.remove(Test.ONE);
+        size = map2.entrySet().size();
+        if (size != 1) {
+            throw new RuntimeException(
+                    "Invalid size in cloned instance. Expected: 1 was: " + size);
+        }
+    }
+}