Java tutorial
/* * Copyright 2002 Sun Microsystems, Inc. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistribution in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * Neither the name of Sun Microsystems, Inc. or the names of * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * This software is provided "AS IS," without a warranty of any * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY * EXCLUDED. SUN AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES * SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR * DISTRIBUTING THE SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN * OR ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR * FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR * PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF * LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE SOFTWARE, * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. * * You acknowledge that Software is not designed, licensed or intended * for use in the design, construction, operation or maintenance of * any nuclear facility. */ package com.sun.j2ee.blueprints.waf.controller.web.flow.handlers; import java.io.ByteArrayInputStream; import java.io.ObjectInputStream; import java.util.Map; import java.util.Iterator; import java.util.HashMap; // Apache Commons- Tag-Lib Imports import org.apache.commons.codec.base64.Base64; // J2EE imports import javax.servlet.http.HttpServletRequest; // WAF imports import com.sun.j2ee.blueprints.waf.controller.web.flow.FlowHandler; import com.sun.j2ee.blueprints.waf.controller.web.flow.FlowHandlerException; /** * This class de-serializes Base64 encoded parameters encoded into a web page using the * ClientCacheLinkTag. * */ public class ClientStateFlowHandler implements FlowHandler { public void doStart(HttpServletRequest request) { } public String processFlow(HttpServletRequest request) throws FlowHandlerException { String forwardScreen = request.getParameter("referring_screen"); // de-serialize the request attributes. Map params = (Map) request.getParameterMap(); HashMap newParams = new HashMap(); String cacheId = request.getParameter("cacheId"); if (!params.isEmpty()) { Iterator it = params.keySet().iterator(); // put the request attributes stored in the session in the request while (it.hasNext()) { String key = (String) it.next(); if (key.startsWith(cacheId + "_attribute_")) { String[] values = (String[]) params.get(key); String valueString = values[0]; byte[] bytes = Base64.decode(valueString.getBytes()); try { ObjectInputStream ois = new ObjectInputStream(new ByteArrayInputStream(bytes)); Object requestObject = requestObject = ois.readObject(); ois.close(); // put the de-serialized object back into the request String requestObjectKey = key.substring((cacheId + "_attribute_").length(), key.length()); request.setAttribute(requestObjectKey, requestObject); } catch (java.io.OptionalDataException ode) { System.err.println("ClientCacheLinkFlowHandler caught: " + ode); } catch (java.lang.ClassNotFoundException cnfe) { System.err.println("ClientCacheLinkFlowHandler caught: " + cnfe); } catch (java.io.IOException iox) { System.err.println("ClientCacheLinkFlowHandler caught: " + iox); } } } } return forwardScreen; } public void doEnd(HttpServletRequest request) { } }