属性＆＃39; addListener＆＃39;在com.chat.viewbeans.ClientBean类型上找不到

Question

我需要A4J推送组件来重复刷新textArea。 xhtml部分是： -

    <a4j:push interval="500" eventProducer="#{clientBean.addListener}"
        reRender="msgArea" id="push"/>

支持bean clientBean如下： -

    @ManagedBean(name="clientBean")
    @SessionScoped
    public class ClientBean {

        public String msg="", input;
        public GossipClient client=new GossipClient();
        public ClientThread thd;
        PushEventListener listener;

        public void addListener(EventListener listener) {
            synchronized (listener) {
                if (this.listener != listener) {
                    this.listener = (PushEventListener) listener;
                }
            }
        }

        public void start() throws UnknownHostException, IOException
        {
            client.connect();
            client.start();
            thd=new ClientThread(this);
            thd.start();
            }
        public void send(){
            client.setSendMessage(input);
        }

        public String getMsg() {
            return msg;
        }

        public void setMsg(String msg) {
            this.msg = msg;
        }

        public String getInput() {
            return input;
        }

        public void setInput(String input) {
            this.input = input;
        }
        public GossipClient getClient() {
            return client;
        }
        public void setClient(GossipClient client) {
            this.client = client;
        }
    }

但是当我转到特定页面时，我收到此错误： -

    exception

    javax.servlet.ServletException: /client.xhtml: Property 'addListener' not found on type com.chat.viewbeans.ClientBean
        javax.faces.webapp.FacesServlet.service(FacesServlet.java:606)
    root cause

    javax.el.ELException: /client.xhtml: Property 'addListener' not found on type com.chat.viewbeans.ClientBean
        com.sun.faces.facelets.compiler.AttributeInstruction.write(AttributeInstruction.java:94)
        com.sun.faces.facelets.compiler.UIInstructions.encodeBegin(UIInstructions.java:82)
        com.sun.faces.facelets.compiler.UILeaf.encodeAll(UILeaf.java:183)
        javax.faces.render.Renderer.encodeChildren(Renderer.java:168)
        javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845)
        javax.faces.component.UIComponent.encodeAll(UIComponent.java:1779)
        javax.faces.component.UIComponent.encodeAll(UIComponent.java:1782)
        com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:402)
        com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:125)
        com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:121)
        com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
        com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
        javax.faces.webapp.FacesServlet.service(FacesServlet.java:594)