org.opencms.flex
Class CmsFlexRequestDispatcher

java.lang.Object
  org.opencms.flex.CmsFlexRequestDispatcher

All Implemented Interfaces:

javax.servlet.RequestDispatcher

public class CmsFlexRequestDispatcher
extends java.lang.Object
implements javax.servlet.RequestDispatcher

Implementation of the RequestDispatcher interface to allow JSPs to be loaded from the OpenCms VFS.

This dispatcher will load data from 3 different data sources:

1. Form the "real" os File system (e.g. for JSP pages)
2. From the OpenCms VFS
3. From the Flex cache

Since:

6.0.0

Version:

$Revision: 1.50 $

Author:

Alexander Kandzior

Constructor Summary

CmsFlexRequestDispatcher(javax.servlet.RequestDispatcher rd, java.lang.String vfs_target, java.lang.String ext_target)
Creates a new instance of CmsFlexRequestDispatcher.

Method Summary

void	forward(javax.servlet.ServletRequest req, javax.servlet.ServletResponse res) Wrapper for the standard servlet API call.
void	include(javax.servlet.ServletRequest req, javax.servlet.ServletResponse res) Wrapper for dispatching to a file from the OpenCms VFS.

Methods inherited from class java.lang.Object

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

Constructor Detail

CmsFlexRequestDispatcher

public CmsFlexRequestDispatcher(javax.servlet.RequestDispatcher rd,
                                java.lang.String vfs_target,
                                java.lang.String ext_target)

Creates a new instance of CmsFlexRequestDispatcher.

Parameters:

rd - the "real" dispatcher, used for include call to file system

vfs_target - the cms resource that represents the external target

ext_target - the external target that the request will be dispatched to

Method Detail

forward

public void forward(javax.servlet.ServletRequest req,
                    javax.servlet.ServletResponse res)
             throws javax.servlet.ServletException,
                    java.io.IOException

Wrapper for the standard servlet API call.

Forward calls are actually NOT wrapped by OpenCms as of now. So they should not be used in JSP pages or servlets.

Specified by:

forward in interface javax.servlet.RequestDispatcher

Parameters:

req - the servlet request

res - the servlet response

Throws:

javax.servlet.ServletException - in case something goes wrong

java.io.IOException - in case something goes wrong

See Also:

RequestDispatcher.forward(javax.servlet.ServletRequest, javax.servlet.ServletResponse)

include

public void include(javax.servlet.ServletRequest req,
                    javax.servlet.ServletResponse res)
             throws javax.servlet.ServletException,
                    java.io.IOException

Wrapper for dispatching to a file from the OpenCms VFS.

This method will dispatch to cache, to real file system or to the OpenCms VFS, whatever is needed.

This method is much more complex than it should be because of the internal standard buffering of JSP pages. Because of that I can not just intercept and buffer the stream, since I don't have access to it (it is wrapped internally in the JSP pages, which have their own buffer). That leads to a solution where the data is first written to the buffered stream, but without includes. Then it is parsed again later in the CmsFlexResponse, enriched with the included elements that have been omitted in the first case. I would love to see a simpler solution, but this works for now.

Specified by:

include in interface javax.servlet.RequestDispatcher

Parameters:

req - the servlet request

res - the servlet response

Throws:

javax.servlet.ServletException - in case something goes wrong

java.io.IOException - in case something goes wrong