Struts example source code file (StrutsRequestWrapper.java)

This example Struts source code file (StrutsRequestWrapper.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Struts tags/keywords

actioncontext, boolean, boolean, http, httpservletrequestwrapper, httpservletrequestwrapper, object, object, request, response, servlet, strutsrequestwrapper, strutsrequestwrapper, valuestack

The Struts StrutsRequestWrapper.java source code

/*
 * $Id: StrutsRequestWrapper.java 651946 2008-04-27 13:41:38Z apetrelli $
 *
 * 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.struts2.dispatcher;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.util.ValueStack;

/**
 * <!-- START SNIPPET: javadoc -->
 *
 * All Struts requests are wrapped with this class, which provides simple JSTL accessibility. This is because JSTL
 * works with request attributes, so this class delegates to the value stack except for a few cases where required to
 * prevent infinite loops. Namely, we don't let any attribute name with "#" in it delegate out to the value stack, as it
 * could potentially cause an infinite loop. For example, an infinite loop would take place if you called:
 * request.getAttribute("#attr.foo").
 *
 * <!-- END SNIPPET: javadoc -->
 *
 */
public class StrutsRequestWrapper extends HttpServletRequestWrapper {

    /**
     * The constructor
     * @param req The request
     */
    public StrutsRequestWrapper(HttpServletRequest req) {
        super(req);
    }

    /**
     * Gets the object, looking in the value stack if not found
     *
     * @param s The attribute key
     */
    public Object getAttribute(String s) {
        if (s != null && s.startsWith("javax.servlet")) {
            // don't bother with the standard javax.servlet attributes, we can short-circuit this
            // see WW-953 and the forums post linked in that issue for more info
            return super.getAttribute(s);
        }

        ActionContext ctx = ActionContext.getContext();
        Object attribute = super.getAttribute(s);
        if (ctx != null) {
            if (attribute == null) {
                boolean alreadyIn = false;
                Boolean b = (Boolean) ctx.get("__requestWrapper.getAttribute");
                if (b != null) {
                    alreadyIn = b.booleanValue();
                }
    
                // note: we don't let # come through or else a request for
                // #attr.foo or #request.foo could cause an endless loop
                if (!alreadyIn && s.indexOf("#") == -1) {
                    try {
                        // If not found, then try the ValueStack
                        ctx.put("__requestWrapper.getAttribute", Boolean.TRUE);
                        ValueStack stack = ctx.getValueStack();
                        if (stack != null) {
                            attribute = stack.findValue(s);
                        }
                    } finally {
                        ctx.put("__requestWrapper.getAttribute", Boolean.FALSE);
                    }
                }
            }
        }
        return attribute;
    }
}