diff options
author | lresende <lresende@13f79535-47bb-0310-9956-ffa450edef68> | 2009-11-11 23:26:33 +0000 |
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committer | lresende <lresende@13f79535-47bb-0310-9956-ffa450edef68> | 2009-11-11 23:26:33 +0000 |
commit | a40e527938d76ba71f211da7e327adb50384ba69 (patch) | |
tree | cb8f99f1727122b040a3f0fbb6649292b6a74302 /sca-java-1.x/tags/1.2/modules/binding-dwr/src/main/java/org/apache/tuscany/sca/binding/dwr/DWRServlet.java | |
parent | 968721109881107520d7aefa91d7fcc0519d7739 (diff) |
Moving 1.x tags
git-svn-id: http://svn.us.apache.org/repos/asf/tuscany@835157 13f79535-47bb-0310-9956-ffa450edef68
Diffstat (limited to 'sca-java-1.x/tags/1.2/modules/binding-dwr/src/main/java/org/apache/tuscany/sca/binding/dwr/DWRServlet.java')
-rw-r--r-- | sca-java-1.x/tags/1.2/modules/binding-dwr/src/main/java/org/apache/tuscany/sca/binding/dwr/DWRServlet.java | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/sca-java-1.x/tags/1.2/modules/binding-dwr/src/main/java/org/apache/tuscany/sca/binding/dwr/DWRServlet.java b/sca-java-1.x/tags/1.2/modules/binding-dwr/src/main/java/org/apache/tuscany/sca/binding/dwr/DWRServlet.java new file mode 100644 index 0000000000..8960ba8d96 --- /dev/null +++ b/sca-java-1.x/tags/1.2/modules/binding-dwr/src/main/java/org/apache/tuscany/sca/binding/dwr/DWRServlet.java @@ -0,0 +1,245 @@ +/* + * 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.tuscany.sca.binding.dwr; + +import java.io.IOException; +import java.io.PrintWriter; +import java.util.ArrayList; +import java.util.Arrays; +import java.util.Collection; +import java.util.Collections; +import java.util.Enumeration; +import java.util.HashMap; +import java.util.List; +import java.util.Map; + +import javax.servlet.ServletConfig; +import javax.servlet.ServletContext; +import javax.servlet.ServletException; +import javax.servlet.ServletRequest; +import javax.servlet.ServletResponse; +import javax.servlet.http.HttpServletRequest; +import javax.servlet.http.HttpServletResponse; + +import org.directwebremoting.Container; +import org.directwebremoting.create.AbstractCreator; +import org.directwebremoting.extend.CreatorManager; +import org.directwebremoting.extend.Handler; +import org.directwebremoting.extend.Remoter; +import org.directwebremoting.servlet.DwrServlet; +import org.directwebremoting.servlet.EngineHandler; +import org.directwebremoting.servlet.PathConstants; +import org.directwebremoting.servlet.UrlProcessor; + +/** + * Tuscany customized DWR Servlet to implement support for the DWR binding + * + * Handles requests for SCA services and references that use <binding.dwr>, + * and also the HTTP GET for the Tuscany DWR system script "scaDomain.js" + */ +public class DWRServlet extends DwrServlet { + private static final long serialVersionUID = 1L; + + transient private Map<String, ServiceHolder> services; + transient private List<String> referenceNames; + transient private boolean initialized; + transient private Map<String, String> initParams; + + private static final String SCADOMAIN_SCRIPT_PATH = "/scaDomain.js"; + + public DWRServlet() { + this.services = new HashMap<String, ServiceHolder>(); + this.referenceNames = new ArrayList<String>(); + + this.initParams = new HashMap<String, String>(); + // maybe use <binding.dwr> attributes to define the init params + initParams.put("activeReverseAjaxEnabled", "true"); + } + + @Override + public void service(ServletRequest req, ServletResponse res) throws ServletException, IOException { + super.service(req, res); + } + + /** + * Initialize the servlet + * There is a single instance of this servlet which is registered + * for multiple path mappings, but the init should only run once. + */ + @Override + public void init(ServletConfig servletConfig) throws ServletException { + if (!initialized) { + super.init(patchConfig(servletConfig)); + addScriptHandler(); + initServices(); + initialized = true; + } + } + + /** + * Add in the handler to process the http get for /sca/scaDomain.js + * + * This wrappers the DWR Engine handler which returns the DWR engine.js script, + * this wrappers that handler so as to add Tuscany specific header and footer code + * to the DWR engine.js to define the Tuscany SCADomain control functions and + * functions for each SCA service and reference that use <binding.dwr>. + */ + private void addScriptHandler() { + + UrlProcessor urlProcessor = (UrlProcessor)getContainer().getBean(UrlProcessor.class.getName()); + + final EngineHandler engineHandler = + (EngineHandler)getContainer().getBean(PathConstants.URL_PREFIX + "/engine.js"); + + final Handler scaDomainScriptHandler = new Handler() { + public void handle(HttpServletRequest request, HttpServletResponse response) throws IOException { + PrintWriter out = response.getWriter(); + out.println("/** Apache Tuscany scaDomain.js Header */"); + + engineHandler.handle(request, response); + + tuscanyFooter(request, out); + } + + }; + + // add the scaDomainScriptHandler to the urlProcessor + // bit of a hack, there's probably cleaner way to get it registered + urlProcessor.afterContainerSetup(new Container() { + public Object getBean(String name) { + return scaDomainScriptHandler; + } + public Collection getBeanNames() { + return Arrays.asList(new String[] {PathConstants.URL_PREFIX + SCADOMAIN_SCRIPT_PATH}); + } + }); + } + + /** + * Adds the JavaScript defining SCADomain, its control functions, + * and functions for all the available SCA services and references. + */ + private void tuscanyFooter(HttpServletRequest request, PrintWriter out) { + out.println("/** Apache Tuscany scaDomain.js Footer */"); + out.println(); + out.println("function scaDomain() { }"); + out.println(); + out.println("// SCA services"); + + // Use the DWR remoter to generate the JavaScipt function for each SCA service + Remoter remoter = (Remoter)getContainer().getBean(Remoter.class.getName()); + + String path = request.getContextPath() + request.getServletPath(); + + for (String serviceName : services.keySet()) { + String serviceScript = remoter.generateInterfaceScript(serviceName, path); + out.println(serviceScript); + } + + if (referenceNames.size() > 0) { + + out.println("// SCA reverse ajax control functions"); + out.println(); + out.println("scaDomain.open = function() { dwr.engine.setActiveReverseAjax(true); };"); + out.println("scaDomain.close = function() { dwr.engine.setActiveReverseAjax(false); };"); + + out.println(); + out.println("// SCA references"); + out.println(); + + // the JavaScript function for SCA references has an + // empty impl as it uses DWR severside "push" + for (String referenceName : referenceNames) { + out.println("function " + referenceName + "() { }"); + } + } + + out.println(); + out.println("/** End of Apache Tuscany scaDomain.js */"); + out.println(); + } + + /** + * Add an SCA reference to be added to the DWR runtime + */ + public void addReference(String name) { + referenceNames.add(name); + } + + /** + * Add an SCA service to be added to the DWR runtime + */ + public void addService(String name, final Class type, final Object instance) { + ServiceHolder holder = new ServiceHolder(); + holder.name = name; + holder.type = type; + holder.instance = instance; + services.put(name, holder); + } + + /** + * Defines each SCA service proxy instance to DWR + */ + private void initServices() { + CreatorManager creatorManager = (CreatorManager)getContainer().getBean(CreatorManager.class.getName()); + + for (final ServiceHolder holder : services.values()) { + creatorManager.addCreator(holder.name, new AbstractCreator() { + public Class getType() { + return holder.type; + } + + public Object getInstance() throws InstantiationException { + return holder.instance; + } + }); + } + } + + // utility class to aid passing around services + private class ServiceHolder { + String name; + Class type; + Object instance; + } + + /** + * Patch the ServletConfig to enable setting init params for DWR + * and so DWR can't see the Tuscany servlet's init params. + */ + private ServletConfig patchConfig(final ServletConfig servletConfig) { + ServletConfig patchedContext = new ServletConfig() { + public String getInitParameter(String name) { + return initParams.get(name); + } + public Enumeration getInitParameterNames() { + return Collections.enumeration(initParams.keySet()); + } + public ServletContext getServletContext() { + return servletConfig.getServletContext(); + } + public String getServletName() { + return servletConfig.getServletName(); + } + }; + return patchedContext; + } + +} |