由Servlet获得FacesContext及ManagedBeans

 　项目中需要通过一链接直接进入JSF生命周期, 苦思冥想无法解决. Google之, 得解. 现帖出那位老外的代码, 很有用的工具类.

　　public abstract class AbstractFacesServlet extends HttpServlet {

　　/** Creates a new instance of AbstractFacesServlet */

　　public AbstractFacesServlet() {

　　super();

　　}

　　public void init(ServletConfig config) throws ServletException {

　　super.init(config);

　　}

　　protected abstract void processRequest(HttpServletRequest request,

　　HttpServletResponse response) throws ServletException, IOException;

　　/**

　　* Handles the HTTP GET method.

　　*

　　* @param request

　　* servlet request

　　* @param response

　　* servlet response

　　*/

　　protected void doGet(HttpServletRequest request,

　　HttpServletResponse response) throws ServletException, IOException {

　　processRequest(request, response);

　　}

　　protected void log(FacesContext facesContext, String message) {

　　facesContext.getExternalContext().log(message);

　　}

　　/**

　　* Handles the HTTP POST method.

　　*

　　* @param request

　　* servlet request

　　* @param response

　　* servlet response

　　*/

　　protected void doPost(HttpServletRequest request,

　　HttpServletResponse response) throws ServletException, IOException {

　　processRequest(request, response);

　　}||| 　　protected FacesContext getFacesContext(HttpServletRequest request,

　　HttpServletResponse response) {

　　FacesContext facesContext = FacesContext.getCurrentInstance();

　　if (facesContext == null) {

　　FacesContextFactory contextFactory = (FacesContextFactory) FactoryFinder

　　.getFactory(FactoryFinder.FACES_CONTEXT_FACTORY);

　　LifecycleFactory lifecycleFactory = (LifecycleFactory) FactoryFinder

　　.getFactory(FactoryFinder.LIFECYCLE_FACTORY);

　　Lifecycle lifecycle = lifecycleFactory

　　.getLifecycle(LifecycleFactory.DEFAULT_LIFECYCLE);

　　facesContext = contextFactory.getFacesContext(request.getSession()

　　.getServletContext(), request, response, lifecycle);

　　// Set using our inner class

　　InnerFacesContext.setFacesContextAsCurrentInstance(facesContext);

　　// set a new viewRoot, otherwise context.getViewRoot returns null

　　UIViewRoot view = facesContext.getApplication().getViewHandler()

　　.createView(facesContext, "cms");

　　facesContext.setViewRoot(view);

　　}

　　return facesContext;

　　}

　　protected Object getBean(String beanName, FacesContext facesContext) {

　　return facesContext.getApplication().getVariableResolver().resolveVariable(facesContext, beanName);

　　}

　　// You need an inner class to be able to call

　　// FacesContext.setCurrentInstance

　　// since it's a protected method

　　private abstract static class InnerFacesContext extends FacesContext {

　　protected static void setFacesContextAsCurrentInstance(

　　FacesContext facesContext) {

　　FacesContext.setCurrentInstance(facesContext);

　　}

　　}

　　}

　　public abstract class AbstractFacesServlet extends HttpServlet {

　　/** Creates a new instance of AbstractFacesServlet */

　　public AbstractFacesServlet() {

　　super();

　　}

　　public void init(ServletConfig config) throws ServletException {

　　super.init(config);

　　}

　　protected abstract void processRequest(HttpServletRequest request,

　　HttpServletResponse response) throws ServletException, IOException;

　　/**

　　* Handles the HTTP GET method.

　　*

　　* @param request

　　* servlet request

　　* @param response

　　* servlet response

　　*/

　　protected void doGet(HttpServletRequest request,

　　HttpServletResponse response) throws ServletException, IOException {

　　processRequest(request, response);

　　}||| 　　protected void log(FacesContext facesContext, String message) {

　　facesContext.getExternalContext().log(message);

　　}

　　/**

　　* Handles the HTTP POST method.

　　*

　　* @param request

　　* servlet request

　　* @param response

　　* servlet response

　　*/

　　protected void doPost(HttpServletRequest request,

　　HttpServletResponse response) throws ServletException, IOException {

　　processRequest(request, response);

　　}

　　protected FacesContext getFacesContext(HttpServletRequest request,

　　HttpServletResponse response) {

　　FacesContext facesContext = FacesContext.getCurrentInstance();

　　if (facesContext == null) {

　　FacesContextFactory contextFactory = (FacesContextFactory) FactoryFinder

　　.getFactory(FactoryFinder.FACES_CONTEXT_FACTORY);

　　LifecycleFactory lifecycleFactory = (LifecycleFactory) FactoryFinder

　　.getFactory(FactoryFinder.LIFECYCLE_FACTORY);

　　Lifecycle lifecycle = lifecycleFactory

　　.getLifecycle(LifecycleFactory.DEFAULT_LIFECYCLE);

　　facesContext = contextFactory.getFacesContext(request.getSession()

　　.getServletContext(), request, response, lifecycle);

　　// Set using our inner class

　　InnerFacesContext.setFacesContextAsCurrentInstance(facesContext);

　　// set a new viewRoot, otherwise context.getViewRoot returns null

　　UIViewRoot view = facesContext.getApplication().getViewHandler()

　　.createView(facesContext, "cms");

　　facesContext.setViewRoot(view);

　　}

　　return facesContext;

　　}

　　protected Object getBean(String beanName, FacesContext facesContext) {

　　return facesContext.getApplication().getVariableResolver().resolveVariable(facesContext, beanName);

　　}

　　// You need an inner class to be able to call

　　// FacesContext.setCurrentInstance

　　// since it's a protected method

　　private abstract static class InnerFacesContext extends FacesContext {

　　protected static void setFacesContextAsCurrentInstance(

　　FacesContext facesContext) {

　　FacesContext.setCurrentInstance(facesContext);

　　}

　　}

　　}

　　后面就不用多说了吧,继承此类,然后实现processRequest方法.考试吧Oracle站编辑整理