我正在使用 JBoss6.1.Final、JSF 2.0 (Mojarra)、Weld CDI、MyFaces CODI 1.0.5（用于视图访问范围）
我正在使用类似于Real World Java EE Patterns Rethinking Best Practices中的网关模式（不幸的是我没有它，所以我可能在这里搞砸了）。基本上，该应用程序允许用户进入“编辑模式”并编辑在具有扩展持久性上下文的 @ViewAccessScoped 支持 bean 中维护的人员列表（创建、编辑、删除），然后单击刷新的“保存”命令链接他们对数据库的所有更改。起初我遇到了 ViewExpiredExceptions 的问题（如果浏览器在会话超时期间空闲，然后执行了进一步的请求），但我添加了一些 jQuery 来向保持会话活动的 servlet 发出 get 请求（称为 10会话超时前的秒数）。这似乎工作但现在我有另一个问题，支持 bean 也是一个 SFSB，经过一段时间的空闲时间，
13:06:22,063 严重 [javax.enterprise.resource.webcontainer.jsf.context] javax.el.ELException：/index.xhtml @27,81 渲染 =“#{!conversationBean.editMode}”：javax.ejb.NoSuchEJBException ：找不到有状态的bean：43h1h2f-9c7qkb-h34t0f34-1-h34teo9p-de
关于如何防止 SFSB 删除或至少更优雅地处理它的任何想法？
这是我的支持bean：
package com.ray.named;
import java.io.Serializable;
import java.util.List;
import javax.annotation.PostConstruct;
import javax.ejb.EJBTransactionRolledbackException;
import javax.ejb.Stateful;
import javax.ejb.TransactionAttribute;
import javax.inject.Named;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.PersistenceContextType;
import org.apache.myfaces.extensions.cdi.core.api.scope.conversation.ViewAccessScoped;
import com.ray.model.Person;
@Named
@Stateful
@ViewAccessScoped
@TransactionAttribute(javax.ejb.TransactionAttributeType.NEVER)
public class ConversationBean implements Serializable {
private static final long serialVersionUID = 1L;
//properties
private List<Person> people;
private String name;
private Boolean editMode;
@PersistenceContext(type=PersistenceContextType.EXTENDED)
private EntityManager em;
@PostConstruct
public void init() {
people = em.createNamedQuery("Person.findAll", Person.class).getResultList();
setEditMode(false);
}
//event listeners
public void beginEdits() {
setEditMode(true);
}
public void addPerson() {
Person p = new Person(name);
em.persist(p);
people.add(p);
name = null;
}
public void removePerson(Person p) {
people.remove(people.indexOf(p));
em.remove(p);
}
//this method flushes the persistence context to the database
@TransactionAttribute(javax.ejb.TransactionAttributeType.REQUIRES_NEW)
public void saveEdits() {
setEditMode(false);
}
//getters/setters
public List<Person> getPeople() {
return people;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Boolean getEditMode() {
return editMode;
}
public void setEditMode(Boolean editMode) {
this.editMode = editMode;
}
}
这是 Person 实体 bean：
package com.ray.model;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.Version;
@Entity
@NamedQueries({
@NamedQuery(name="Person.findAll",
query="SELECT p FROM Person p")
})
public class Person {
@Id @GeneratedValue(strategy=GenerationType.IDENTITY)
private Integer id;
private String name;
@Version
private int version;
public Person() { }
public Person(String name) {
setName(name);
}
public boolean equals(Object o) {
if (!(o instanceof Person)) {
return false;
}
return id == ((Person)o).id;
}
//getters/setters
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getId() {
return id;
}
public int getVersion() {
return version;
}
public void setVersion(int version) {
this.version = version;
}
}
这是视图：
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:ui="http://java.sun.com/jsf/facelets">
<h:head>
<script src="http://code.jquery.com/jquery-latest.min.js"></script>
<script>
$(document).ready(function() {
setInterval(function() {
$.get("#{request.contextPath}/poll");
}, #{(session.maxInactiveInterval - 10) * 1000});
});
</script>
<title>Conversation Test</title>
</h:head>
<h:body>
<h:form>
<h:commandLink value="Begin Edits" rendered="#{!conversationBean.editMode}">
<f:ajax render="@form" listener="#{conversationBean.beginEdits}"/>
</h:commandLink>
<h:commandLink value="Save" rendered="#{conversationBean.editMode}">
<f:ajax render="@form" listener="#{conversationBean.saveEdits}"/>
</h:commandLink>
<h:dataTable id="peopleTable" value="#{conversationBean.people}" var="person">
<h:column>
<f:facet name="header">Name</f:facet>
<h:panelGroup>
<h:inputText value="#{person.name}" disabled="#{!conversationBean.editMode}">
<f:ajax/>
</h:inputText>
<h:commandLink value="X" disabled="#{!conversationBean.editMode}">
<f:ajax render="@form" listener="#{conversationBean.removePerson(person)}"/>
</h:commandLink>
</h:panelGroup>
</h:column>
</h:dataTable>
<h:panelGrid columns="2">
<h:outputLabel for="name">Name:</h:outputLabel>
<h:inputText id="name" value="#{conversationBean.name}" disabled="#{!conversationBean.editMode}"/>
</h:panelGrid>
<h:commandButton value="Add" disabled="#{!conversationBean.editMode}">
<f:ajax execute="@form" render="@form" listener="#{conversationBean.addPerson}"/>
</h:commandButton>
</h:form>
</h:body>
</html>
这是一个用于保持会话活动的 servlet（在会话过期前 10 秒由 jQuery ajax 获取请求调用）：
package com.ray.web;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class PollServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public void init() throws ServletException {
}
public String getServletInfo() {
return null;
}
public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
request.getSession(); //Keep session alive
}
public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
}
public void destroy() {
}
}