org.apache.shale.dialog.faces
Class DialogNavigationHandler

java.lang.Object
  javax.faces.application.NavigationHandler
      org.apache.shale.dialog.faces.DialogNavigationHandler

public final class DialogNavigationHandler
extends javax.faces.application.NavigationHandler

An implementation of NavigationHandler that provides support for dialog management according to the rules specified below. It delegates handling to the standard implementation when there is no current dialog, or when an unrecognized outcome is returned.

• When handleNavigation() is called with a logical outcome of the form dialog:xxx, and there is no current dialog in progress, the Dialog with name xxx is selected, and the specified starting state is selected.
• If the current state is an ActionState, a MethodBinding is created, and the specified method is called. The returned outcome is used to transition to another state within this dialog.
• If the current state is a SubdialogState, the current position is pushed onto a stack, and the dialog specified by the SubdialogState is entered at its specified starting state. When the EndState for the subordinate dialog returns an outcome, the previous state is popped from the stack, and the outcome is used to transition to another state within this dialog.
• If the current state is a ViewState, the specified view identifier will be used to create a new JavaServer Faces view, and then cause it to be rendered. When the subsequent form submit is performed, and handleNavigation() is called again, the logical outcome (returned by whatever action method was invoked) will be used to select the transition to the next state in the current dialog.
• If the current state is an EndState, processing proceeds depending upon whether or not there is a view identifier specified:
  • If there is a view identifier specified, it is created and rendered, as for a ViewState. When the subseqeent form submit is performed, the parent dialog will be popped from the stack, and this outcome will be passed to it for transition processing (if there is no parent dialog, this outcome will be delegated to the standard navigation handler).
  • If there is no view identifier specified, the outcome that triggered transition to this state will be passed to the parent dialog (if any) or delegated to the standard navigation handler.

$Id: DialogNavigationHandler.java 419431 2006-07-06 04:38:39Z wsmoak $

Field Summary

static String	PREFIX The default prefix on a logical outcome String that indicates the remainder of the string is the name of a Dialog to be entered.
static Class[]	SIGNATURE Parameter signature for the method bindings we create for an ActionState.

Constructor Summary

DialogNavigationHandler(javax.faces.application.NavigationHandler handler)
Create a new DialogNavigationHandler, wrapping the specified standard navigation handler implementation.

Method Summary

void	handleNavigation(javax.faces.context.FacesContext context, String fromAction, String outcome) Handle the navigation request implied by the specified parameters.

Methods inherited from class java.lang.Object

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

Field Detail

PREFIX

public static final String PREFIX

The default prefix on a logical outcome String that indicates the remainder of the string is the name of a Dialog to be entered. The actual value used can be set by defining a context initialization parameter for key Globals.PREFIX.

See Also:

Constant Field Values

SIGNATURE

public static final Class[] SIGNATURE

Parameter signature for the method bindings we create for an ActionState.

Constructor Detail

DialogNavigationHandler

public DialogNavigationHandler(javax.faces.application.NavigationHandler handler)

Create a new DialogNavigationHandler, wrapping the specified standard navigation handler implementation.

Parameters:

handler - Standard NavigationHandler we are wrapping

Method Detail

handleNavigation

public void handleNavigation(javax.faces.context.FacesContext context,
                             String fromAction,
                             String outcome)

Handle the navigation request implied by the specified parameters.

Specified by:

handleNavigation in class javax.faces.application.NavigationHandler

Parameters:

context - FacesContext for the current request

fromAction - The action binding expression that was evaluated to retrieve the specified outcome (if any)

outcome - The logical outcome returned by the specified action

Throws:

IllegalArgumentException - if the configuration information for a previously saved position cannot be found

IllegalArgumentException - if an unknown State type is found