From de74482fe8dffcf6eed62438244cb08ddbc3f442 Mon Sep 17 00:00:00 2001
From: Inderjeet Singh <inder123@gmail.com>
Date: Mon, 12 Jul 2010 22:13:38 +0000
Subject: [PATCH] Implemented hashCode and equals for TypedKey to make it a
 value object. Asserted preconditions on constructor input.

---
 .../gson/webservice/definition/TypedKey.java  | 29 +++++++++++++++++++
 .../webservice/definition/TypedKeyTest.java   | 23 +++++++++++++++
 2 files changed, 52 insertions(+)
 create mode 100644 wsdef/src/test/java/com/google/gson/webservice/definition/TypedKeyTest.java

diff --git a/wsdef/src/main/java/com/google/gson/webservice/definition/TypedKey.java b/wsdef/src/main/java/com/google/gson/webservice/definition/TypedKey.java
index 0556b55c..baa43a15 100644
--- a/wsdef/src/main/java/com/google/gson/webservice/definition/TypedKey.java
+++ b/wsdef/src/main/java/com/google/gson/webservice/definition/TypedKey.java
@@ -27,6 +27,9 @@ public class TypedKey<T> {
   private final Class<T> classOfT;
 
   public TypedKey(String name, Class<T> classOfT) {
+    Preconditions.checkNotNull(name);
+    Preconditions.checkNotNull(classOfT);
+
     this.name = name;
     this.classOfT = classOfT;
   }
@@ -38,4 +41,30 @@ public class TypedKey<T> {
   public Class<T> getClassOfT() {
     return classOfT;
   }
+
+  
+  @Override
+  public int hashCode() {
+    return name.hashCode() + classOfT.getCanonicalName().hashCode() >> 1;
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    if (this == obj) {
+      return true;
+    }
+    if (obj == null) {
+      return false;
+    }
+    if (getClass() != obj.getClass()) {
+      return false;
+    }
+    TypedKey<?> other = (TypedKey<?>) obj;
+    return name.equals(other.name) && classOfT.equals(other.classOfT);
+  }
+
+  @Override
+  public String toString() {
+    return String.format("{name:%s, classOfT:%s}", name, classOfT);
+  }
 }
diff --git a/wsdef/src/test/java/com/google/gson/webservice/definition/TypedKeyTest.java b/wsdef/src/test/java/com/google/gson/webservice/definition/TypedKeyTest.java
new file mode 100644
index 00000000..309f3aa4
--- /dev/null
+++ b/wsdef/src/test/java/com/google/gson/webservice/definition/TypedKeyTest.java
@@ -0,0 +1,23 @@
+// Copyright 2010 Google Inc. All Rights Reserved.
+
+package com.google.gson.webservice.definition;
+
+import junit.framework.TestCase;
+
+/**
+ * Unit tests for {@link TypedKey}
+ *
+ * @author inder
+ */
+public class TypedKeyTest extends TestCase {
+
+  public void testEqualsForSameName() {
+    assertEquals(new TypedKey<String>("name", String.class),
+        new TypedKey<String>(new String("name"), String.class));
+  }
+
+  public void testEqualsFailsForDifferentClasses() {
+    assertFalse(new TypedKey<Object>("name", Object.class).equals(
+        new TypedKey<String>("name", String.class)));
+  }
+}