javax.el.PropertyNotFoundException：/role.xhtml @ 20,63 value =“＃{roleBean.rolepojo.role}”：目标无法访问，'rolepojo'返回null

Question

这里我试图使用Hibernate会话工厂将角色插入到数据库中， 现在我的问题是当我试图插入数据时，它说错误

错误：

  WARNING: /role.xhtml @20,63 value="#{roleBean.rolepojo.role}": Target Unreachable, 'rolepojo' returned null
    javax.el.PropertyNotFoundException: /role.xhtml @20,63 value="#{roleBean.rolepojo.role}": Target Unreachable, 'rolepojo' returned null

我已经实现了所有属性，任何人都可以在我出错的地方提供帮助。

PrimeFaces代码：

    <ui:composition 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"
        xmlns:p="http://primefaces.org/ui"
        xmlns:c="http://java.sun.com/jsp/jstl/core"
        template="/WEB-INF/template.xhtml">

     <ui:define name="implementation">
            <link rel="stylesheet" href="http://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" />
            <script src="http://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>

            <div class="container-fluid ui-fluid">
               <h:form id="roleUpdateForm" >

            <p:messages id="msgs" />

            <p:panelGrid columns="2" cellpadding="5" styleClass="ui-responsive" id="roleData">
                <h:outputLabel value="Roles : *" />
                <p:inputText  value="#{roleBean.rolepojo.role}" />

                <h:outputLabel  value="Role Description : *" />
                <p:inputTextarea rows="6" cols="33" value="#{roleBean.rolepojo.description}"/>

                <h:outputLabel  value="Start Date : *" />

                <p:calendar styleClass="start-emp" value="#{roleBean.rolepojo.startDate}" timeZone="IST"  pattern="dd/MM/yyyy" requiredMessage="Pls Enter Start Date"/>


                <h:outputLabel  value="End Date : *" />

                    <p:calendar styleClass="start-emp" value="#{roleBean.rolepojo.endDate}" timeZone="IST"  pattern="dd/MM/yyyy"  requiredMessage="Pls Enter End Date"/>



                <f:facet name="footer">
                    <p:commandButton value="Save" 
actionListener="#{roleBean.saveRole}" 
 icon="ui-icon-check" 
rendered="#{empty roleBean.rolepojo.id}"
 update=":roleUpdateForm:role"/>

<p:commandButton value="Update" actionListener="#{roleBean.updateRole}" icon="ui-icon-check" rendered="#{0 lt roleBean.rolepojo.id}" update=":roleUpdateForm:role"/>
                    <p:commandButton value="New" actionListener="#{roleBean.newRole}" icon="ui-icon-check" rendered="#{0 lt roleBean.rolepojo.id}" update=":roleUpdateForm:roleData"/>
                </f:facet>
            </p:panelGrid>




     <p:growl id="msges" showDetail="true"/>
       <p:dataTable id="role" var="roleListStack" value="#{roleBean.roleList}" style="margin:20px auto;width:400px;" 
                    selectionMode="single" selection="#{roleBean.rolepojo}" rowKey="#{roleListStack.id}">
           <f:facet name="header">
               Role Listing
           </f:facet>

            <p:ajax event="rowSelect" update=":roleUpdateForm:roleData" />
            <p:ajax event="rowUnselect"  update=":roleUpdateForm:roleData" />

            <p:column headerText="S.No" >
              <h:outputText value="#{roleListStack.id}" />
           </p:column>

            <p:column headerText="Role Name" >
              <h:outputText value="#{roleListStack.role}" />
           </p:column>

            <p:column headerText="Role Description" >
              <h:outputText value="#{roleListStack.description}" />
           </p:column>
            <p:column headerText="Role Start Date" >
              <h:outputText value="#{roleListStack.startDate}" />
           </p:column>
            <p:column headerText="Role End Date" >
              <h:outputText value="#{roleListStack.endDate}" />
           </p:column>

       </p:dataTable>

       </h:form>
            </div>
        </ui:define>

RoleBean代码：

package com.ihub.beans;

import java.util.List;

import javax.annotation.PostConstruct;
import javax.faces.application.FacesMessage;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.ManagedProperty;
import javax.faces.bean.SessionScoped;
import javax.faces.context.FacesContext;
import javax.faces.event.ActionEvent;

import org.primefaces.context.RequestContext;
import org.primefaces.event.SelectEvent;
import org.primefaces.event.UnselectEvent;

import com.ihub.pojo.Organization;
import com.ihub.pojo.Role;
import com.ihub.service.RoleService;

@ManagedBean
@SessionScoped
public class RoleBean {
    @ManagedProperty("#{roleService}")
    private RoleService roleService;

    private List<Role> roleList;

    private Role rolepojo;

    @PostConstruct
    public void init(){
        //System.out.println("in bean init");
        rolepojo = new Role();
        roleList = roleService.getList(Role.class);
        //System.out.println(rolepojo.getId()+ " rolepojo.getId()");
    }


    public void saveRole(ActionEvent event){ 
    System.out.println(" in Role save func");
    //System.out.println(rolepojo.getRole());

        roleService.saveRoleService(rolepojo);
    //  System.out.println("Role save"+rolepojo.getRole());
        FacesContext.getCurrentInstance().addMessage(null, new FacesMessage("Role","Role Created Successfully"));

    }

    public void updateRole(ActionEvent event){
        System.out.println("action event");

        roleService.updateRole(rolepojo);
    }

    public void newRole(ActionEvent event){
        RequestContext.getCurrentInstance().reset("roleUpdateForm:roleData");
    }


    public Role getRolepojo() {
        return rolepojo;
    }
    public void setRolepojo(Role rolepojo) {
        this.rolepojo = rolepojo;
    }

    public List<Role> getRoleList() {
        return roleList;
    }
    public void setRoleList(List<Role> roleList) {
        this.roleList = roleList;
    }

    public RoleService getRoleService() {
        return roleService;
    }

    public void setRoleService(RoleService roleService) {
        this.roleService = roleService;
    }


}

Pojo课程：

package com.ihub.pojo;

import java.util.Date;

public class Role {
    private int id;
    private String role;
    private String description;
    private Date startDate;
    private Date endDate;


    public Role(int id, String role, String description) {
        super();
        this.id = id;
        this.role = role;
        this.description = description;
    }
    public Role(String role, String description) {
        super();

        this.role = role;
        this.description = description;
    }
     public Role() {
        // TODO Auto-generated constructor stub
    }



    public int getId() {
        //System.out.println("from role id"+ id);
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getRole() {
        return role;
    }
    public void setRole(String role) {
        this.role = role;
    }
    public String getDescription() {
        return description;
    }
    public void setDescription(String description) {
        this.description = description;
    }
    public Date getStartDate() {
        return startDate;
    }
    public void setStartDate(Date startDate) {
        this.startDate = startDate;
    }
    public Date getEndDate() {
        return endDate;
    }
    public void setEndDate(Date endDate) {
        this.endDate = endDate;
    }
}