Expose JsonObject size.

gson/src/main/java/com/google/gson/JsonObject.java

@@ -132,6 +132,15 @@ public final class JsonObject extends JsonElement {
     return members.entrySet();
   }
 
+  /**
+   * Returns the number of key/value pairs in the object.
+   *
+   * @return the number of key/value pairs in the object.
+   */
+  public int size() {
+    return members.size();
+  }
+
   /**
    * Convenience method to check if a member with the specified name is present in this object.
    *

gson/src/test/java/com/google/gson/JsonObjectTest.java

@@ -158,6 +158,20 @@ public class JsonObjectTest extends TestCase {
     assertFalse(b.equals(a));
   }
 
+  public void testSize() {
+    JsonObject o = new JsonObject();
+    assertEquals(0, o.size());
+
+    o.add("Hello", new JsonPrimitive(1));
+    assertEquals(1, o.size());
+
+    o.add("Hi", new JsonPrimitive(1));
+    assertEquals(2, o.size());
+
+    o.remove("Hello");
+    assertEquals(1, o.size());
+  }
+
   public void testDeepCopy() {
     JsonObject original = new JsonObject();
     JsonArray firstEntry = new JsonArray();