Class ConcatServlet

  extended by javax.servlet.GenericServlet
      extended by javax.servlet.http.HttpServlet
          extended by org.eclipse.jetty.servlets.ConcatServlet
All Implemented Interfaces:
Serializable, Servlet, ServletConfig

public class ConcatServlet
extends HttpServlet

Concatenation Servlet 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&/chat/chat.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 206 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
Method Summary
protected  void doGet(HttpServletRequest req, HttpServletResponse resp)
protected  long getLastModified(HttpServletRequest req)
 void init()
Methods inherited from class javax.servlet.http.HttpServlet
doDelete, doHead, doOptions, doPost, doPut, doTrace, service, service
Methods inherited from class javax.servlet.GenericServlet
destroy, getInitParameter, getInitParameterNames, getServletConfig, getServletContext, getServletInfo, getServletName, init, log, log
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail


public ConcatServlet()
Method Detail


public void init()
          throws ServletException
init in class GenericServlet


protected long getLastModified(HttpServletRequest req)
getLastModified in class HttpServlet


protected void doGet(HttpServletRequest req,
                     HttpServletResponse resp)
              throws ServletException,
doGet in class HttpServlet

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