Package org.eclipse.jetty.servlets

Class ConcatServlet

java.lang.Object

javax.servlet.GenericServlet

javax.servlet.http.HttpServlet

org.eclipse.jetty.servlets.ConcatServlet

All Implemented Interfaces:

Servlet, ServletConfig

public class ConcatServlet
extends HttpServlet

This servlet may be used to concatenate multiple resources into a single response.

It is intended to be used to load multiple javascript or css files, but may be used for any content of the same mime type that can be meaningfully concatenated.

The servlet uses RequestDispatcher.include(javax.servlet.ServletRequest, javax.servlet.ServletResponse) to combine the requested content, so dynamically generated content may be combined (Eg engine.js for DWR).

The servlet uses parameter names of the query string as resource names relative to the context root. So these script tags:

 <script type="text/javascript" src="../js/behaviour.js"></script>
 <script type="text/javascript" src="../js/ajax.js"></script>
 <script type="text/javascript" src="../chat/chat.js"></script>
 

can be replaced with the single tag (with the ConcatServlet mapped to /concat):

 <script type="text/javascript" src="../concat?/js/behaviour.js&/js/ajax.js&/chat/chat.js"></script>
 

The ServletContext.getMimeType(String) method is used to determine the mime type of each resource. If the types of all resources do not match, then a 415 UNSUPPORTED_MEDIA_TYPE error is returned.

If the init parameter development is set to true then the servlet will run in development mode and the content will be concatenated on every request.

Otherwise the init time of the servlet is used as the lastModifiedTime of the combined content and If-Modified-Since requests are handled with 304 NOT Modified responses if appropriate. This means that when not in development mode, the servlet must be restarted before changed content will be served.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
ConcatServlet()

Method Summary

Modifier and Type	Method	Description
protected void	doGet(HttpServletRequest request, HttpServletResponse response)
protected long	getLastModified(HttpServletRequest req)
void	init()

Methods inherited from class javax.servlet.GenericServlet

destroy, getInitParameter, getInitParameterNames, getServletConfig, getServletContext, getServletInfo, getServletName, init, log, log

Methods inherited from class javax.servlet.http.HttpServlet

doDelete, doHead, doOptions, doPost, doPut, doTrace, service, service

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ConcatServlet

public ConcatServlet()

Method Detail

init

public void init()
          throws ServletException

Overrides:

init in class GenericServlet

Throws:

ServletException

getLastModified

protected long getLastModified(HttpServletRequest req)

Overrides:

getLastModified in class HttpServlet

doGet

protected void doGet(HttpServletRequest request,
                     HttpServletResponse response)
              throws ServletException,
                     java.io.IOException

Overrides:

doGet in class HttpServlet

Throws:

ServletException

java.io.IOException