/*
* 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.server.communication;
import java.io.IOException;
import java.io.Serializable;
import java.io.Writer;
import java.util.Collection;
import com.vaadin.server.AbstractClientConnector;
import com.vaadin.server.ClientConnector;
import com.vaadin.server.LegacyCommunicationManager;
import com.vaadin.server.PaintException;
import com.vaadin.ui.UI;
import elemental.json.Json;
import elemental.json.JsonArray;
import elemental.json.JsonException;
import elemental.json.JsonObject;
import elemental.json.impl.JsonUtil;
/**
* Serializes a connector hierarchy to JSON.
*
* @author Vaadin Ltd
* @since 7.1
*/
public class ConnectorHierarchyWriter implements Serializable {
/**
* Writes a JSON object containing the connector hierarchy (parent-child
* mappings) of the dirty connectors in the given UI.
*
* @param ui
* The {@link UI} whose hierarchy to write.
* @param writer
* The {@link Writer} used to write the JSON.
* @throws IOException
* If the serialization fails.
*/
public void write(UI ui, Writer writer) throws IOException {
Collection<ClientConnector> dirtyVisibleConnectors = ui
.getConnectorTracker().getDirtyVisibleConnectors();
JsonObject hierarchyInfo = Json.createObject();
for (ClientConnector connector : dirtyVisibleConnectors) {
String connectorId = connector.getConnectorId();
JsonArray children = Json.createArray();
for (ClientConnector child : AbstractClientConnector
.getAllChildrenIterable(connector)) {
if (LegacyCommunicationManager
.isConnectorVisibleToClient(child)) {
children.set(children.length(), child.getConnectorId());
}
}
try {
hierarchyInfo.put(connectorId, children);
} catch (JsonException e) {
throw new PaintException(
"Failed to send hierarchy information about "
+ connectorId + " to the client: "
+ e.getMessage(), e);
}
}
writer.write(JsonUtil.stringify(hierarchyInfo));
}
}