NavigationHandler (Java EE 5)

Java EE API

previous page next page

Overview

Package

Class

Tree

Deprecated

Index

Help

PREV CLASS NEXT CLASS

FRAMES NO FRAMES

SUMMARY: NESTED | FIELD | CONSTR | METHOD

DETAIL: FIELD | CONSTR | METHOD

javax.faces.application Class NavigationHandler

java.lang.Object
  javax.faces.application.NavigationHandler

public abstract class NavigationHandler
extends Object

此应用程序调用的应用程序操作返回的结果字符串会传递给 NavigationHandler，它将使用此结果（以及相关的状态信息）选择接着显示的视图。

NavigationHandler 的默认实现必须由 JSF 实现提供，将一直使用此方法，除非调用 setNavigationHandler() 建立不同的实现。此默认实例将当前视图的视图标识符、指定的操作绑定和指定结果与 faces-config.xml 文件中提供的任何导航规则进行比较。如果有导航情况匹配，则将通过调用 FacesContext.setViewRoot() 更改当前视图。注意，null 结果值永远不会匹配任何导航规则，因此它可以用作指示符，指示应重新显示当前视图。

英文文档：

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 JSF implementation, which will be utilized unless setNavigationHandler() is called to establish a different one. 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.

Constructor Summary
`NavigationHandler()`

Method Summary
`abstract void`	`handleNavigation(FacesContext context, String fromAction, String outcome)` Perform navigation processing based on the state information in the specified `FacesContext`, plus the outcome string returned by an executed application action.

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Constructor Detail

public NavigationHandler()

英文文档：
NavigationHandler

public NavigationHandler()

Method Detail

abstract public void handleNavigation(FacesContext context, String fromAction, String outcome)

根据指定 `FacesContext` 中的状态信息以及已执行的应用程序操作返回的结果字符串执行导航处理。

context 当前请求的 `FacesContext`

fromAction 对其求值以获取指定结果的操作绑定表达式；如果通过其他方法获得结果，则为 `null`

outcome 以前调用的应用程序操作返回的逻辑结果（可以为 `null`）

Throws NullPointerException: 如果 `context` 为 `null`

英文文档：
handleNavigation

public abstract void handleNavigation(FacesContext context,
                                      String fromAction,
                                      String outcome)

Perform navigation processing based on the state information in the specified FacesContext, plus the outcome string returned by an executed application action.

Parameters:: context - The FacesContext for the current request; fromAction - The action binding expression that was evaluated to retrieve the specified outcome, or null if the outcome was acquired by some other means; outcome - The logical outcome returned by a previous invoked application action (which may be null)
Throws:: NullPointerException - if context is null