Package org.zkoss.zk.ui.sys

Interface PageRenderPatch

public interface PageRenderPatch

A patch that is used to process the rendering result of a page. Currently, it is used only by DHtmlLayoutPortlet to allow the deployer to plug-in a patch for particular portal container.

To specify a patch, use a library property called "org.zkoss.zk.portlet.PageRenderPatch.class" (refer to Attributes.PORTLET_RENDER_PATCH_CLASS.

Since:

5.0.0

Author:

tomyeh

Method Summary

Modifier and Type	Method	Description
java.io.Writer	beforeRender(RequestInfo reqInfo)	Called before rendering to test if the patch shall be applied.
void	patchRender(RequestInfo reqInfo, Page page, java.io.Writer result, java.io.Writer out)	Called after rendering to patch the result.

Method Detail

beforeRender

java.io.Writer beforeRender(RequestInfo reqInfo)

Called before rendering to test if the patch shall be applied.

Parameters:

reqInfo - the request information

Returns:

null if no need of patch, or a writer if the patch is required. The writer will be used to hold the rendering result of the portlet. Thus, you can process it later in patchRender(org.zkoss.zk.ui.sys.RequestInfo, org.zkoss.zk.ui.Page, java.io.Writer, java.io.Writer) (so the writer is usually an instance of StringWriter).

patchRender

void patchRender(RequestInfo reqInfo,
                 Page page,
                 java.io.Writer result,
                 java.io.Writer out)
          throws java.io.IOException

Called after rendering to patch the result. If beforeRender(org.zkoss.zk.ui.sys.RequestInfo) returns null, this method won't be called since nothing to patch.

If beforeRender(org.zkoss.zk.ui.sys.RequestInfo) returns a writer, the writer will become the result argument.

Parameters:

reqInfo - the request information

result - the result returned by beforeRender(org.zkoss.zk.ui.sys.RequestInfo), and the rendering result of a page will be written to it.

out - the real output sent to the client. It is the writer to write the patched result to.

Throws:

java.io.IOException