Debug JSf LifeCycle

You can use a PhaseListener to trace the phases of the JSF lifecycle and execute some processes where required. But you can also use a "dummy" PhaseListener to debug the phases to see what is happening in which phase. Here is a basic example of such a LifeCycleListener:

package mypackage;

import javax.faces.event.PhaseEvent;

import javax.faces.event.PhaseId;

import javax.faces.event.PhaseListener; 

public class LifeCycleListener implements PhaseListener { 

    public PhaseId getPhaseId() {

        return PhaseId.ANY_PHASE;

    } 

    public void beforePhase(PhaseEvent event) {

        System.out.println("START PHASE " + event.getPhaseId());

    } 

    public void afterPhase(PhaseEvent event) {

        System.out.println("END PHASE " + event.getPhaseId());

    } 

}

Add the following lines to the faces-config.xml to activate the LifeCycleListener.

    mypackage.LifeCycleListener

This produces like the following in the system output:
START PHASE RESTORE_VIEW 1
END PHASE RESTORE_VIEW 1
START PHASE APPLY_REQUEST_VALUES 2
END PHASE APPLY_REQUEST_VALUES 2
START PHASE PROCESS_VALIDATIONS 3
END PHASE PROCESS_VALIDATIONS 3
START PHASE UPDATE_MODEL_VALUES 4
END PHASE UPDATE_MODEL_VALUES 4
START PHASE INVOKE_APPLICATION 5
END PHASE INVOKE_APPLICATION 5
START PHASE RENDER_RESPONSE 6
END PHASE RENDER_RESPONSE 6