Add a convenience base class for value type locators
Review at http://gwt-code-reviews.appspot.com/1428809
git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@10131 8db76d5a-ed1c-0410-87a9-c151d255dfc7
diff --git a/user/src/com/google/web/bindery/requestfactory/shared/ValueLocator.java b/user/src/com/google/web/bindery/requestfactory/shared/ValueLocator.java
new file mode 100644
index 0000000..f32b112
--- /dev/null
+++ b/user/src/com/google/web/bindery/requestfactory/shared/ValueLocator.java
@@ -0,0 +1,59 @@
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * 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 com.google.web.bindery.requestfactory.shared;
+
+/**
+ * A {@link Locator} for use with value types (as opposed to entities), which
+ * are not persisted. Abstract methods from the {@link Locator} class that are
+ * not relevant for value types are implemented to return {@code null}.
+ *
+ * @param <T> the type of domain object the Locator will operate on
+ */
+public abstract class ValueLocator<T> extends Locator<T, Void> {
+
+ /**
+ * Returns {@code null}.
+ */
+ @Override
+ public final Class<T> getDomainType() {
+ return null;
+ }
+
+ /**
+ * Returns {@code null}.
+ */
+ @Override
+ public final Void getId(T domainObject) {
+ return null;
+ }
+
+ /**
+ * Returns {@code null}.
+ */
+ @Override
+ public final Class<Void> getIdType() {
+ return null;
+ }
+
+ /**
+ * Returns {@code null}.
+ */
+ @Override
+ public final Object getVersion(T domainObject) {
+ return null;
+ }
+}
