/*
* $Id$
*
* 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 com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.util.logging.Logger;
import com.opensymphony.xwork2.util.logging.LoggerFactory;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.nio.charset.Charset;
/**
* <!-- START SNIPPET: description -->
*
* A result that send the content out as plain text. Useful typically when needed
* to display the raw content of a JSP or Html file for example.
*
* <!-- END SNIPPET: description -->
*
*
* <!-- START SNIPPET: params -->
*
* <ul>
* <li>location (default) = location of the file (jsp/html) to be displayed as plain text.</li>
* <li>charSet (optional) = character set to be used. This character set will be used to set the
* response type (eg. Content-Type=text/plain; charset=UTF-8) and when reading
* using a Reader. Some example of charSet would be UTF-8, ISO-8859-1 etc.
* </ul>
*
* <!-- END SNIPPET: params -->
*
*
* <pre>
* <!-- START SNIPPET: example -->
*
* <action name="displayJspRawContent" >
* <result type="plainText">/myJspFile.jsp</result>
* </action>
*
*
* <action name="displayJspRawContent" >
* <result type="plainText">
* <param name="location">/myJspFile.jsp</param>
* <param name="charSet">UTF-8</param>
* </result>
* </action>
*
* <!-- END SNIPPET: example -->
* </pre>
*
*/
public class PlainTextResult extends StrutsResultSupport {
public static final int BUFFER_SIZE = 1024;
private static final Logger LOG = LoggerFactory.getLogger(PlainTextResult.class);
private static final long serialVersionUID = 3633371605905583950L;
private String charSet;
public PlainTextResult() {
super();
}
public PlainTextResult(String location) {
super(location);
}
/**
* Set the character set
*
* @return The character set
*/
public String getCharSet() {
return charSet;
}
/**
* Set the character set
*
* @param charSet The character set
*/
public void setCharSet(String charSet) {
this.charSet = charSet;
}
/* (non-Javadoc)
* @see org.apache.struts2.dispatcher.StrutsResultSupport#doExecute(java.lang.String, com.opensymphony.xwork2.ActionInvocation)
*/
protected void doExecute(String finalLocation, ActionInvocation invocation) throws Exception {
// verify charset
Charset charset = readCharset();
HttpServletResponse response = (HttpServletResponse) invocation.getInvocationContext().get(HTTP_RESPONSE);
applyCharset(charset, response);
applyAdditionalHeaders(response);
String location = adjustLocation(finalLocation);
PrintWriter writer = response.getWriter();
InputStreamReader reader = null;
try {
InputStream resourceAsStream = readStream(invocation, location);
logWrongStream(finalLocation, resourceAsStream);
if (charset != null) {
reader = new InputStreamReader(resourceAsStream, charset);
} else {
reader = new InputStreamReader(resourceAsStream);
}
if (resourceAsStream != null) {
sendStream(writer, reader);
}
} finally {
if (reader != null)
reader.close();
if (writer != null) {
writer.flush();
writer.close();
}
}
}
protected InputStream readStream(ActionInvocation invocation, String location) {
ServletContext servletContext = (ServletContext) invocation.getInvocationContext().get(SERVLET_CONTEXT);
return servletContext.getResourceAsStream(location);
}
protected void logWrongStream(String finalLocation, InputStream resourceAsStream) {
if (resourceAsStream == null) {
if (LOG.isWarnEnabled()) {
LOG.warn("Resource at location [" + finalLocation + "] cannot be obtained (return null) from ServletContext !!! ");
}
}
}
protected void sendStream(PrintWriter writer, InputStreamReader reader) throws IOException {
char[] buffer = new char[BUFFER_SIZE];
int charRead;
while((charRead = reader.read(buffer)) != -1) {
writer.write(buffer, 0, charRead);
}
}
protected String adjustLocation(String location) {
if (location.charAt(0) != '/') {
return "/" + location;
}
return location;
}
protected void applyAdditionalHeaders(HttpServletResponse response) {
response.setHeader("Content-Disposition", "inline");
}
protected void applyCharset(Charset charset, HttpServletResponse response) {
if (charset != null) {
response.setContentType("text/plain; charset=" + charSet);
} else {
response.setContentType("text/plain");
}
}
protected Charset readCharset() {
Charset charset = null;
if (charSet != null) {
if (Charset.isSupported(charSet)) {
charset = Charset.forName(charSet);
} else {
if (LOG.isWarnEnabled()) {
LOG.warn("charset [" + charSet + "] is not recognized ");
}
charset = null;
}
}
return charset;
}
}