Fix Enum equals to work correctly by reflection

bug 28180, from Matthias Eichel


git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/lang/trunk@137837 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/commons/lang/enums/Enum.java

@@ -228,8 +228,9 @@
  * @author Stephen Colebourne
  * @author Chris Webb
  * @author Mike Bowler
- * @since 1.0
- * @version $Id: Enum.java,v 1.1 2004/02/23 04:34:20 ggregory Exp $
+ * @author Matthias Eichel
+ * @since 2.1 (class existed in enum package from v1.0)
+ * @version $Id: Enum.java,v 1.2 2004/06/01 20:54:57 scolebourne Exp $
  */
 public abstract class Enum implements Comparable, Serializable {
 
@@ -537,7 +538,10 @@ public final boolean equals(Object other) {
             // classes are in the same class loader.
             return iName.equals(((Enum) other).iName);
         } else {
-            // This and other are in different class loaders, we must use reflection.
+            // This and other are in different class loaders, we must check indirectly
+            if (other.getClass().getName().equals(this.getClass().getName()) == false) {
+                return false;
+            }
             try {
                 Method mth = other.getClass().getMethod("getName", null);
                 String name = (String) mth.invoke(other, null);

src/test/org/apache/commons/lang/enums/EnumEqualsTest.java

@@ -0,0 +1,90 @@
+/*
+ * Copyright 2004 The Apache Software Foundation.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.lang.enums;
+
+import junit.framework.Test;
+import junit.framework.TestCase;
+import junit.framework.TestSuite;
+
+/**
+ * Test cases for the {@link Enum} class equals method.
+ *
+ * @author Matthias Eichel
+ * @author Stephen Colebourne
+ * @version $Id: EnumEqualsTest.java,v 1.1 2004/06/01 20:54:57 scolebourne Exp $
+ */
+public final class EnumEqualsTest extends TestCase {
+
+    public EnumEqualsTest(String name) {
+        super(name);
+    }
+
+    public void setUp() {
+    }
+
+    public static Test suite() {
+        TestSuite suite = new TestSuite(EnumEqualsTest.class);
+        suite.setName("Enum equals Tests");
+        return suite;
+    }
+
+    //-----------------------------------------------------------------------
+    static final class CarColorEnum extends Enum {
+        public static final CarColorEnum BLACK = new CarColorEnum("black");
+        public static final CarColorEnum BROWN = new CarColorEnum("brown");
+        public static final CarColorEnum YELLOW = new CarColorEnum("yellow");
+        public static final CarColorEnum BLUE = new CarColorEnum("blue");
+        public static final CarColorEnum RED = new CarColorEnum("red");
+
+        private CarColorEnum(String enumAsString) {
+            super(enumAsString);
+        }
+    }
+
+    static final class TrafficlightColorEnum extends Enum {
+        public static final TrafficlightColorEnum RED = new TrafficlightColorEnum("red");
+        public static final TrafficlightColorEnum YELLOW = new TrafficlightColorEnum("yellow");
+        public static final TrafficlightColorEnum GREEN = new TrafficlightColorEnum("green");
+
+        private TrafficlightColorEnum(String enumAsString) {
+            super(enumAsString);
+        }
+    }
+
+    static class TotallyUnrelatedClass {
+        private final String name;
+
+        public TotallyUnrelatedClass(final String name) {
+            this.name = name;
+        }
+
+        public String getName() {
+            return name;
+        }
+    }
+
+    //-----------------------------------------------------------------------
+    public void testEquals() {
+        assertEquals(false, CarColorEnum.RED.equals(TrafficlightColorEnum.RED));
+        assertEquals(false, CarColorEnum.YELLOW.equals(TrafficlightColorEnum.YELLOW));
+        
+        assertEquals(false, TrafficlightColorEnum.RED.equals(new TotallyUnrelatedClass("red")));
+        assertEquals(false, CarColorEnum.RED.equals(new TotallyUnrelatedClass("red")));
+        
+        assertEquals(false, TrafficlightColorEnum.RED.equals(new TotallyUnrelatedClass("some")));
+        assertEquals(false, CarColorEnum.RED.equals(new TotallyUnrelatedClass("some")));
+    }
+}

src/test/org/apache/commons/lang/enums/EnumTestSuite.java

@@ -24,7 +24,7 @@
  * Test suite for the Enum package.
  *
  * @author <a href="mailto:scolebourne@joda.org">Stephen Colebourne</a>
- * @version $Id: EnumTestSuite.java,v 1.1 2004/02/23 04:34:20 ggregory Exp $
+ * @version $Id: EnumTestSuite.java,v 1.2 2004/06/01 20:54:57 scolebourne Exp $
  */
 public class EnumTestSuite extends TestCase {
     
@@ -49,6 +49,7 @@ public static Test suite() {
         TestSuite suite = new TestSuite();
         suite.setName("Commons-Lang-Enum Tests");
         suite.addTest(EnumTest.suite());
+        suite.addTest(EnumEqualsTest.suite());
         suite.addTest(EnumUtilsTest.suite());
         suite.addTest(ValuedEnumTest.suite());
         return suite;