org.apache.struts2.dispatcher.StrutsRequestWrapper Maven / Gradle / Ivy
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* 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
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* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
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*/
package org.apache.struts2.dispatcher;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.util.ValueStack;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import static org.apache.commons.lang3.BooleanUtils.isTrue;
/**
*
*
* 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").
*
*
*
*/
public class StrutsRequestWrapper extends HttpServletRequestWrapper {
private static final String REQUEST_WRAPPER_GET_ATTRIBUTE = "__requestWrapper.getAttribute";
private final boolean disableRequestAttributeValueStackLookup;
/**
* The constructor
* @param req The request
*/
public StrutsRequestWrapper(HttpServletRequest req) {
this(req, false);
}
/**
* The constructor
* @param req The request
* @param disableRequestAttributeValueStackLookup flag for disabling request attribute value stack lookup (JSTL accessibility)
*/
public StrutsRequestWrapper(HttpServletRequest req, boolean disableRequestAttributeValueStackLookup) {
super(req);
this.disableRequestAttributeValueStackLookup = disableRequestAttributeValueStackLookup;
}
/**
* Gets the object, looking in the value stack if not found
*
* @param key The attribute key
*/
public Object getAttribute(String key) {
if (key == null) {
throw new NullPointerException("You must specify a key value");
}
if (disableRequestAttributeValueStackLookup || key.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(key);
}
ActionContext ctx = ActionContext.getContext();
Object attribute = super.getAttribute(key);
if (ctx != null && attribute == null) {
boolean alreadyIn = isTrue((Boolean) ctx.get(REQUEST_WRAPPER_GET_ATTRIBUTE));
// note: we don't let # come through or else a request for
// #attr.foo or #request.foo could cause an endless loop
if (!alreadyIn && !key.contains("#")) {
try {
// If not found, then try the ValueStack
ctx.put(REQUEST_WRAPPER_GET_ATTRIBUTE, Boolean.TRUE);
ValueStack stack = ctx.getValueStack();
if (stack != null) {
attribute = stack.findValue(key);
}
} finally {
ctx.put(REQUEST_WRAPPER_GET_ATTRIBUTE, Boolean.FALSE);
}
}
}
return attribute;
}
}