Custom Viewhandler for JBoss 7.1 - jsf

Question

I want to implement a custom ViewHandler. Currently I'm only forwarding all calls to the default Viewhandler, but if I enable this ViewHandler in my faces-config.xml, the preRenderView event type (and maybe other functionality) is broken. Does anybody no what I'm doing wrong?
I'm using JBoss AS 7.1.1.
Thanks.
public class ReverseProxyViewHandler extends ViewHandler {
ViewHandler defaultHandler;
public ReverseProxyViewHandler(ViewHandler defaultHandler) {
this.defaultHandler = defaultHandler;
}
#Override
public Locale calculateLocale(FacesContext context) {
return defaultHandler.calculateLocale(context);
}
#Override
public String calculateRenderKitId(FacesContext context) {
return defaultHandler.calculateRenderKitId(context);
}
#Override
public UIViewRoot createView(FacesContext context, String viewId) {
return defaultHandler.createView(context, viewId);
}
#Override
public String getActionURL(FacesContext context, String path) {
return defaultHandler.getActionURL(context, path);
}
#Override
public String getResourceURL(FacesContext context, String path) {
return defaultHandler.getResourceURL(context, path);
}
#Override
public void renderView(FacesContext context, UIViewRoot viewToRender) throws IOException, FacesException {
defaultHandler.renderView(context, viewToRender);
}
#Override
public UIViewRoot restoreView(FacesContext context, String viewId) {
return defaultHandler.restoreView(context, viewId);
}
#Override
public void writeState(FacesContext context) throws IOException {
defaultHandler.writeState(context);
}
}

Answer 1

I had the same error, but by extending the ViewHandlerWrapper instead of the the ViewHandler I got it to work.
Here is an example of my CustomViewHandler (not a complete example, but was built within our app as a proof of concept) :
import javax.faces.application.ViewExpiredException;
import javax.faces.application.ViewHandler;
import javax.faces.application.ViewHandlerWrapper;
import javax.faces.component.UIViewRoot;
import javax.faces.context.FacesContext;
import org.apache.log4j.Logger;
public class CustomViewHandler extends ViewHandlerWrapper {
private ViewHandler wrapped;
private static Logger LOGGER = Logger.getLogger(CustomViewHandler.class);
public CustomViewHandler(ViewHandler wrapped) {
LOGGER.info("CustomViewHandler.CustomViewHandler():wrapped View Handler:"+wrapped.getClass());
this.wrapped = wrapped;
}
#Override
public UIViewRoot restoreView(FacesContext context, String viewId) {
UIViewRoot root;
try {
LOGGER.info("restoring view : " + viewId);
root = wrapped.restoreView(context, viewId);
} catch (ViewExpiredException e) {
LOGGER.error("View Expired : " + e.getMessage() + " -> recreating");
root = wrapped.createView(context, viewId);
}
return root;
}
#Override
public ViewHandler getWrapped() {
return wrapped;
}
}
If you want a more complete and functional custom view handler, look at the OmniFaces RestorableViewHandler. Source code is available on that page.
From Java Doc
javax.faces.application.ViewHandlerWrapper
Provides a simple implementation of ViewHandler that can be subclassed by developers >wishing to provide specialized behavior to an existing ViewHandler instance. The default >implementation of all methods is to call through to the wrapped ViewHandler.
Usage: extend this class and override getWrapped to return the instance we are wrapping.