Refactor Grid SelectionModels as extensions (#18624)

This patch removes all selection related variables and API from several
core parts of Grid.

Change-Id: Idb7aa48fda69ded1ef58a69c1f7dbc78b7f52a54

WebContent/release-notes.html

@@ -119,6 +119,8 @@ <h3 id="incompatible">Incompatible or Behavior-altering Changes in @version-mino
                 This may interfere with custom response compression solutions that do not respect the Content-Encoding response header.</li>
             <li>Unused methods related to the "out of sync" message have been removed from SystemMessages class.</li>
             <li>All notifications use the WAI-ARIA alert role to be compatible with Jaws</li>
+            <li>Grid SelectionModels are now Extensions. This update removes all selection related variables and API from 
+            GridConnector, GridState, GridServerRpc and GridClientRpc</li>
         </ul>
         <h3 id="knownissues">Known Issues and Limitations</h3>
         <ul>

client/src/com/vaadin/client/connectors/AbstractSelectionModelConnector.java

@@ -0,0 +1,82 @@
+/*
+ * 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.client.connectors;
+
+import java.util.Collection;
+
+import com.vaadin.client.data.DataSource.RowHandle;
+import com.vaadin.client.extensions.AbstractExtensionConnector;
+import com.vaadin.client.widget.grid.selection.SelectionModel;
+import com.vaadin.client.widgets.Grid;
+import com.vaadin.shared.ui.grid.GridState;
+
+import elemental.json.JsonObject;
+
+/**
+ * Base class for all selection model connectors.
+ * 
+ * @since
+ * @author Vaadin Ltd
+ */
+public abstract class AbstractSelectionModelConnector<T extends SelectionModel<JsonObject>>
+        extends AbstractExtensionConnector {
+
+    @Override
+    public GridConnector getParent() {
+        return (GridConnector) super.getParent();
+    }
+
+    protected Grid<JsonObject> getGrid() {
+        return getParent().getWidget();
+    }
+
+    protected RowHandle<JsonObject> getRowHandle(JsonObject row) {
+        return getGrid().getDataSource().getHandle(row);
+    }
+
+    protected String getRowKey(JsonObject row) {
+        return row != null ? getParent().getRowKey(row) : null;
+    }
+
+    protected abstract T createSelectionModel();
+
+    public abstract static class AbstractSelectionModel implements
+            SelectionModel<JsonObject> {
+
+        @Override
+        public boolean isSelected(JsonObject row) {
+            return row.hasKey(GridState.JSONKEY_SELECTED);
+        }
+
+        @Override
+        public void setGrid(Grid<JsonObject> grid) {
+            // NO-OP
+        }
+
+        @Override
+        public void reset() {
+            // Should not need any actions.
+        }
+
+        @Override
+        public Collection<JsonObject> getSelectedRows() {
+            throw new UnsupportedOperationException(
+                    "This client-side selection model "
+                            + getClass().getSimpleName()
+                            + " does not know selected rows.");
+        }
+    }
+}