Introduce initial data source support for Grid (#12878)

Change-Id: I2d1b2e4a797b2dac9ee97c832fcd40fb472edc08

2 files changed, 110 insertions, 0 deletions

diff --git a/server/src/com/vaadin/data/RpcDataProviderExtension.java b/server/src/com/vaadin/data/RpcDataProviderExtension.java
new file mode 100644
index 0000000000..48f03b98c0
--- /dev/null
+++ b/server/src/com/vaadin/data/RpcDataProviderExtension.java
@@ -0,0 +1,101 @@
+/*
+ * Copyright 2000-2013 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.data;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+import com.vaadin.data.Container.Indexed;
+import com.vaadin.server.AbstractExtension;
+import com.vaadin.shared.data.DataProviderRpc;
+import com.vaadin.shared.data.DataProviderState;
+import com.vaadin.shared.data.DataRequestRpc;
+import com.vaadin.ui.components.grid.Grid;
+
+/**
+ * Provides Vaadin server-side container data source to a
+ * {@link com.vaadin.client.ui.grid.GridConnector}. This is currently
+ * implemented as an Extension hardcoded to support a specific connector type.
+ * This will be changed once framework support for something more flexible has
+ * been implemented.
+ * 
+ * @since 7.2
+ * @author Vaadin Ltd
+ */
+public class RpcDataProviderExtension extends AbstractExtension {
+
+    private final Indexed container;
+
+    /**
+     * Creates a new data provider using the given container.
+     * 
+     * @param container
+     *            the container to make available
+     */
+    public RpcDataProviderExtension(Indexed container) {
+        this.container = container;
+
+        // TODO support for reacting to events from the container added later
+
+        registerRpc(new DataRequestRpc() {
+            @Override
+            public void requestRows(int firstRow, int numberOfRows) {
+                pushRows(firstRow, numberOfRows);
+            }
+        });
+
+        getState().containerSize = container.size();
+    }
+
+    private void pushRows(int firstRow, int numberOfRows) {
+        List<?> itemIds = container.getItemIds(firstRow, numberOfRows);
+        Collection<?> propertyIds = container.getContainerPropertyIds();
+        List<String[]> rows = new ArrayList<String[]>(itemIds.size());
+        for (Object itemId : itemIds) {
+            Item item = container.getItem(itemId);
+            String[] row = new String[propertyIds.size()];
+
+            int i = 0;
+            for (Object propertyId : propertyIds) {
+                Object value = item.getItemProperty(propertyId).getValue();
+                String stringValue = String.valueOf(value);
+                row[i++] = stringValue;
+            }
+
+            rows.add(row);
+        }
+
+        getRpcProxy(DataProviderRpc.class).setRowData(firstRow, rows);
+    }
+
+    @Override
+    protected DataProviderState getState() {
+        return (DataProviderState) super.getState();
+    }
+
+    /**
+     * Makes the data source available to the given {@link Grid} component.
+     * 
+     * @param component
+     *            the remote data grid component to extend
+     */
+    public void extend(Grid component) {
+        super.extend(component);
+    }
+
+}
diff --git a/server/src/com/vaadin/ui/components/grid/Grid.java b/server/src/com/vaadin/ui/components/grid/Grid.java
index 2b19043d93..79cc05e1a0 100644
--- a/server/src/com/vaadin/ui/components/grid/Grid.java
+++ b/server/src/com/vaadin/ui/components/grid/Grid.java
@@ -29,6 +29,7 @@ import com.vaadin.data.Container;
 import com.vaadin.data.Container.PropertySetChangeEvent;
 import com.vaadin.data.Container.PropertySetChangeListener;
 import com.vaadin.data.Container.PropertySetChangeNotifier;
+import com.vaadin.data.RpcDataProviderExtension;
 import com.vaadin.server.KeyMapper;
 import com.vaadin.shared.ui.grid.ColumnGroupRowState;
 import com.vaadin.shared.ui.grid.GridColumnState;
@@ -107,6 +108,8 @@ public class Grid extends AbstractComponent {
         }
     };
 
+    private RpcDataProviderExtension datasourceExtension;
+
     /**
      * Creates a new Grid using the given datasource.
      * 
@@ -140,7 +143,13 @@ public class Grid extends AbstractComponent {
                     .removePropertySetChangeListener(propertyListener);
         }
 
+        if (datasourceExtension != null) {
+            removeExtension(datasourceExtension);
+        }
+
         datasource = container;
+        datasourceExtension = new RpcDataProviderExtension(container);
+        datasourceExtension.extend(this);
 
         // Listen to changes in properties and remove columns if needed
         if (datasource instanceof PropertySetChangeNotifier) {