Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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 org.apache.wicket.page; import java.util.Collection; import org.apache.wicket.Component; import org.apache.wicket.Page; import org.apache.wicket.request.Response; import org.apache.wicket.request.cycle.RequestCycle; import org.apache.wicket.request.http.WebResponse; import org.apache.wicket.util.string.Strings; /** * A {@link PartialPageUpdate} that serializes itself to XML. */ public class XmlPartialPageUpdate extends PartialPageUpdate { /** * The name of the root element in the produced XML document. */ public static final String START_ROOT_ELEMENT = "<ajax-response>"; public static final String END_ROOT_ELEMENT = "</ajax-response>"; public XmlPartialPageUpdate(final Page page) { super(page); } @Override public void setContentType(WebResponse response, String encoding) { response.setContentType("text/xml; charset=" + encoding); } @Override protected void writeHeader(Response response, String encoding) { response.write("<?xml version=\"1.0\" encoding=\""); response.write(encoding); response.write("\"?>"); response.write(START_ROOT_ELEMENT); } @Override protected void writeComponent(Response response, String markupId, Component component, String encoding) { // substitute our encoding response for the old one so we can capture // component's markup in a manner safe for transport inside CDATA block Response oldResponse = RequestCycle.get().setResponse(bodyBuffer); try { // render any associated headers of the component writeHeaderContribution(response, component); bodyBuffer.reset(); try { component.renderPart(); } catch (RuntimeException e) { bodyBuffer.reset(); throw e; } } finally { // Restore original response RequestCycle.get().setResponse(oldResponse); } response.write("<component id=\""); response.write(markupId); response.write("\" ><![CDATA["); response.write(encode(bodyBuffer.getContents())); response.write("]]></component>"); bodyBuffer.reset(); } @Override protected void writeFooter(Response response, String encoding) { response.write(END_ROOT_ELEMENT); } @Override protected void writeHeaderContribution(Response response) { CharSequence contents = headerBuffer.getContents(); if (Strings.isEmpty(contents) == false) { response.write("<header-contribution>"); // we need to write response as CDATA and parse it on client, // because konqueror crashes when there is a <script> element response.write("<![CDATA[<head xmlns:wicket=\"http://wicket.apache.org\">"); response.write(encode(contents)); response.write("</head>]]>"); response.write("</header-contribution>"); } } @Override protected void writeNormalEvaluations(final Response response, final Collection<CharSequence> scripts) { writeEvaluations(response, "evaluate", scripts); } @Override protected void writePriorityEvaluations(Response response, Collection<CharSequence> scripts) { writeEvaluations(response, "priority-evaluate", scripts); } private void writeEvaluations(final Response response, String elementName, Collection<CharSequence> scripts) { if (scripts.size() > 0) { StringBuilder combinedScript = new StringBuilder(1024); for (CharSequence script : scripts) { combinedScript.append("(function(){").append(script).append("})();"); } writeEvaluation(elementName, response, combinedScript); } } /** * @param invocation * type of invocation tag, usually {@literal evaluate} or * {@literal priority-evaluate} * @param response * @param js */ private void writeEvaluation(final String invocation, final Response response, final CharSequence js) { response.write("<"); response.write(invocation); response.write(">"); response.write("<![CDATA["); response.write(encode(js)); response.write("]]>"); response.write("</"); response.write(invocation); response.write(">"); bodyBuffer.reset(); } protected CharSequence encode(CharSequence str) { return Strings.replaceAll(str, "]]>", "]]]]><![CDATA[>"); } }