jakarta.faces.application.NavigationHandler Maven / Gradle / Ivy
/*
* Copyright (c) 1997, 2020 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package jakarta.faces.application;
import jakarta.faces.context.FacesContext;
/**
*
* A NavigationHandler is passed the
* outcome string returned by an application action invoked for this application, and will use this (along with related
* state information) to choose the view to be displayed next.
*
*
*
* A default implementation of NavigationHandler must be provided by the Jakarta Server Faces
* implementation, which will be utilized unless setNavigationHandler() is called to establish a different
* one. An implementation of this class must be thread-safe. This default
* instance will compare the view identifier of the current view, the specified action binding, and the specified
* outcome against any navigation rules provided in faces-config.xml file(s). If a navigation case matches,
* the current view will be changed by a call to FacesContext.setViewRoot(). Note that a null
* outcome value will never match any navigation rule, so it can be used as an indicator that the current view should be
* redisplayed.
*
*/
public abstract class NavigationHandler {
/**
*
* Perform navigation processing based on the state information in the
* specified {@link FacesContext}, plus the outcome string returned by an executed application action.
*
*
*
* If the implementation class also extends {@link ConfigurableNavigationHandler}, the implementation must guarantee
* that the logic used in a call to {@link ConfigurableNavigationHandler#getNavigationCase} is used in this method to
* determine the correct navigation.
*
*
*
* This method must set the render targets (used in partial rendering) to render all invoking
* {@link jakarta.faces.context.PartialViewContext#setRenderAll}) if the view identifier has changed as the result of an
* application action (to take into account Ajax requests).
*
*
* @param context The {@link FacesContext} for the current request
* @param fromAction The action binding expression that was evaluated to retrieve the specified outcome, or
* null if the outcome was acquired by some other means
* @param outcome The logical outcome returned by a previous invoked application action (which may be null)
*
* @throws NullPointerException if context is null
*/
public abstract void handleNavigation(FacesContext context, String fromAction, String outcome);
/**
*
* Overloaded variant of
* {@link #handleNavigation(jakarta.faces.context.FacesContext, java.lang.String, java.lang.String)} that allows the
* caller to provide the defining document id for a flow to be entered by this navigation. For backward compatibility
* with decorated {@code NavigationHandler} implementations that conform to an earlier version of the specification, an
* implementation is provided that calls through to
* {@link #handleNavigation(jakarta.faces.context.FacesContext, java.lang.String, java.lang.String)}, ignoring the
* {@code toFlowDocumentId} parameter.
*
*
* @param context The {@link FacesContext} for the current request
* @param fromAction The action binding expression that was evaluated to retrieve the specified outcome, or
* null if the outcome was acquired by some other means
* @param outcome The logical outcome returned by a previous invoked application action (which may be null)
* @param toFlowDocumentId The defining document id of the flow into which this navigation will cause entry.
*
* @throws NullPointerException if context is null
*/
public void handleNavigation(FacesContext context, String fromAction, String outcome, String toFlowDocumentId) {
this.handleNavigation(context, fromAction, outcome);
}
}