/*
* $Id$
*
* 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 java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts2.ServletActionContext;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.Result;
import com.opensymphony.xwork2.util.TextParseUtil;
import com.opensymphony.xwork2.util.ValueStack;
/**
* <!-- START SNIPPET: description -->
*
* A custom Result type for setting HTTP headers and status by optionally evaluating against the ValueStack.
* This result can also be used to send and error to the client.
*
* <!-- END SNIPPET: description -->
* <p/>
* <b>This result type takes the following parameters:</b>
*
* <!-- START SNIPPET: params -->
*
* <ul>
*
* <li><b>status</b> - the http servlet response status code that should be set on a response.</li>
*
* <li><b>parse</b> - true by default. If set to false, the headers param will not be parsed for Ognl expressions.</li>
*
* <li><b>headers</b> - header values.</li>
*
* <li><b>error</b> - the http servlet response error code that should be set on a response.</li>
*
* <li><b>errorMessage</b> - error message to be set on response if 'error' is set.</li>
* </ul>
*
* <!-- END SNIPPET: params -->
*
* <b>Example:</b>
*
* <pre><!-- START SNIPPET: example -->
* <result name="success" type="httpheader">
* <param name="status">204</param>
* <param name="headers.a">a custom header value</param>
* <param name="headers.b">another custom header value</param>
* </result>
*
* <result name="proxyRequired" type="httpheader">
* <param name="error">305</param>
* <param name="errorMessage">this action must be accessed through a prozy</param>
* </result>
* <!-- END SNIPPET: example --></pre>
*
*/
public class HttpHeaderResult implements Result {
private static final long serialVersionUID = 195648957144219214L;
/** The default parameter */
public static final String DEFAULT_PARAM = "status";
private boolean parse = true;
private Map<String,String> headers;
private int status = -1;
private int error = -1;
private String errorMessage;
public HttpHeaderResult() {
super();
headers = new HashMap<String,String>();
}
public HttpHeaderResult(int status) {
this();
this.status = status;
this.parse = false;
}
/**
* Sets the http servlet error code that should be set on the reponse
*
* @param error the Http error code
* @see javax.servlet.http.HttpServletResponse#sendError(int)
*/
public void setError(int error) {
this.error = error;
}
/**
* Sets the error message that should be set on the reponse
*
* @param errorMessage error message send to the client
* @see javax.servlet.http.HttpServletResponse#sendError(int, String)
*/
public void setErrorMessage(String errorMessage) {
this.errorMessage = errorMessage;
}
/**
* Returns a Map of all HTTP headers.
*
* @return a Map of all HTTP headers.
*/
public Map getHeaders() {
return headers;
}
/**
* Sets whether or not the HTTP header values should be evaluated against the ValueStack (by default they are).
*
* @param parse <tt>true</tt> if HTTP header values should be evaluated agains the ValueStack, <tt>false</tt>
* otherwise.
*/
public void setParse(boolean parse) {
this.parse = parse;
}
/**
* Sets the http servlet response status code that should be set on a response.
*
* @param status the Http status code
* @see javax.servlet.http.HttpServletResponse#setStatus(int)
*/
public void setStatus(int status) {
this.status = status;
}
/**
* Adds an HTTP header to the response
* @param name
* @param value
*/
public void addHeader(String name, String value) {
headers.put(name, value);
}
/**
* Sets the optional HTTP response status code and also re-sets HTTP headers after they've
* been optionally evaluated against the ValueStack.
*
* @param invocation an encapsulation of the action execution state.
* @throws Exception if an error occurs when re-setting the headers.
*/
public void execute(ActionInvocation invocation) throws Exception {
HttpServletResponse response = ServletActionContext.getResponse();
ValueStack stack = ActionContext.getContext().getValueStack();
if (status != -1) {
response.setStatus(status);
} else if (error != -1) {
if (errorMessage != null) {
String finalMessage = parse ? TextParseUtil.translateVariables(
errorMessage, stack) : errorMessage;
response.sendError(error, finalMessage);
} else
response.sendError(error);
}
if (headers != null) {
for (Iterator iterator = headers.entrySet().iterator();
iterator.hasNext();) {
Map.Entry entry = (Map.Entry) iterator.next();
String value = (String) entry.getValue();
String finalValue = parse ? TextParseUtil.translateVariables(value, stack) : value;
response.addHeader((String) entry.getKey(), finalValue);
}
}
}
}