123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115 |
- /*
- * Copyright 2000-2016 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 java.util.Set;
-
- import com.vaadin.server.AbstractClientConnector;
- import com.vaadin.server.ClientConnector;
- import com.vaadin.server.LegacyCommunicationManager;
- import com.vaadin.server.PaintException;
- import com.vaadin.server.VaadinRequest;
- import com.vaadin.server.VaadinService;
- 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.
- * @param stateUpdateConnectors
- * connector ids with state changes
- * @throws IOException
- * If the serialization fails.
- */
- public void write(UI ui, Writer writer, Set<String> stateUpdateConnectors)
- 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());
- }
- }
-
- // Omit for leaf nodes with state changes
- if (children.length() > 0
- || !stateUpdateConnectors.contains(connectorId)) {
- try {
- hierarchyInfo.put(connectorId, children);
- } catch (JsonException e) {
- throw new PaintException(
- "Failed to send hierarchy information about "
- + connectorId + " to the client: "
- + e.getMessage(),
- e);
- }
- }
- }
- // Dummy assert just for conditionally storing away data that will be
- // used by the real assert later on
- assert storeSentHierarchy(hierarchyInfo, stateUpdateConnectors);
-
- writer.write(JsonUtil.stringify(hierarchyInfo));
- }
-
- private boolean storeSentHierarchy(JsonObject hierarchyInfo,
- Set<String> stateUpdateConnectors) {
- VaadinRequest request = VaadinService.getCurrentRequest();
- if (request != null) {
- request.setAttribute(
- ConnectorHierarchyWriter.class.getName() + ".hierarchyInfo",
- hierarchyInfo);
- request.setAttribute(ConnectorHierarchyWriter.class.getName()
- + ".stateUpdateConnectors", stateUpdateConnectors);
- }
-
- // Always true, we're just setting up for another assert
- return true;
- }
-
- }
|