Split AbstractGridExtension from AbstractRenderer (#18003)

Change-Id: Ibe5766cde606091ce2bd58055472fa7cf3f21374

2 files changed, 73 insertions, 5 deletions

diff --git a/server/src/com/vaadin/ui/Grid.java b/server/src/com/vaadin/ui/Grid.java
index 902098e8d0..2c7e63ddf8 100644
--- a/server/src/com/vaadin/ui/Grid.java
+++ b/server/src/com/vaadin/ui/Grid.java
@@ -3274,15 +3274,15 @@ public class Grid extends AbstractComponent implements SelectionNotifier,
     /**
      * An abstract base class for server-side Grid renderers.
      * {@link com.vaadin.client.widget.grid.Renderer Grid renderers}. This class
-     * currently extends the AbstractExtension superclass, but this fact should
-     * be regarded as an implementation detail and subject to change in a future
-     * major or minor Vaadin revision.
+     * currently extends the AbstractGridExtension superclass, but this fact
+     * should be regarded as an implementation detail and subject to change in a
+     * future major or minor Vaadin revision.
      * 
      * @param <T>
      *            the type this renderer knows how to present
      */
-    public static abstract class AbstractRenderer<T> extends AbstractExtension
-            implements Renderer<T> {
+    public static abstract class AbstractRenderer<T> extends
+            AbstractGridExtension implements Renderer<T> {
 
         private final Class<T> presentationType;
 
@@ -3340,6 +3340,33 @@ public class Grid extends AbstractComponent implements SelectionNotifier,
             return JsonCodec.encode(value, null, type,
                     getUI().getConnectorTracker()).getEncodedValue();
         }
+    }
+
+    /**
+     * An abstract base class for server-side Grid extensions.
+     * 
+     * @since
+     */
+    public static abstract class AbstractGridExtension extends
+            AbstractExtension {
+
+        /**
+         * Constructs a new Grid extension.
+         */
+        public AbstractGridExtension() {
+            super();
+        }
+
+        /**
+         * Constructs a new Grid extension and extends given Grid.
+         * 
+         * @param grid
+         *            a grid instance
+         */
+        public AbstractGridExtension(Grid grid) {
+            super();
+            extend(grid);
+        }
 
         /**
          * Gets the item id for a row key.
diff --git a/server/tests/src/com/vaadin/tests/server/component/grid/GridExtensionTest.java b/server/tests/src/com/vaadin/tests/server/component/grid/GridExtensionTest.java
new file mode 100644
index 0000000000..d9db217aa3
--- /dev/null
+++ b/server/tests/src/com/vaadin/tests/server/component/grid/GridExtensionTest.java
@@ -0,0 +1,41 @@
+/*
+ * Copyright 2000-2014 Vaadin Ltd.
+ * 
+ * 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.vaadin.tests.server.component.grid;
+
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+import com.vaadin.ui.Grid;
+import com.vaadin.ui.Grid.AbstractGridExtension;
+
+public class GridExtensionTest {
+
+    public static class DummyGridExtension extends AbstractGridExtension {
+
+        public DummyGridExtension(Grid grid) {
+            super(grid);
+        }
+    }
+
+    @Test
+    public void testCreateExtension() {
+        Grid grid = new Grid();
+        DummyGridExtension dummy = new DummyGridExtension(grid);
+        assertTrue("DummyGridExtension never made it to Grid", grid
+                .getExtensions().contains(dummy));
+    }
+}