在容器外使用EJB 3.0 Persistence

　　Lucas Jellema 最近写了篇文章，名字叫：Getting Started with EJB 3.0 Persistence out-of-container using the Reference Implementation （GlassFish）。

　　该文介绍了如何在J2EE Container之外使用EJB 3.0 Persistence，实现了service类和data model.

　　Lucas Jellema提到的步骤如下：

　　1.和安装 5 （JDK 5.0/JRE 5.0）

　　2.和配置 GlassFish

　　GlassFish：

　　3.创建Entities - POJOs with annotations that link them to database objects

　　比如其中的员工类：

package nl.amis.ejb30.hrm;

import java.io.Serializable;

import java.sql.Timestamp;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name="EMP")
public class Employee implements Serializable {
    private Double comm;

    private Long deptno;

    private Long empno;

    private String ename;

    private Timestamp hiredate;

    private String job;

    private Long mgr;

    private Double sal;

    public Employee() {
    }

    public Employee(Long empno) {
        this.empno = empno;
    }

    @Column(name="COMM")
    public Double getComm() {
        return comm;
    }

    public void setComm(Double comm) {
        this.comm = comm;
    }

    @Column(name="DEPTNO")
    public Long getDeptno() {
        return deptno;
    }

    public void setDeptno(Long deptno) {
        this.deptno = deptno;
    }

    @Id
    @Column(name="EMPNO", nullable=false)
    public Long getEmpno() {
        return empno;
    }

    public void setEmpno(Long empno) {
        this.empno = empno;
    }

    @Column(name="ENAME")
    public String getEname() {
        return ename;
    }

    public void setEname(String ename) {
        this.ename = ename;
    }

    @Column(name="HIREDATE")
    public Timestamp getHiredate() {
        return hiredate;
    }

    public void setHiredate(Timestamp hiredate) {
        this.hiredate = hiredate;
    }

    @Column(name="JOB")
    public String getJob() {
        return job;
    }

    public void setJob(String job) {
        this.job = job;
    }

    @Column(name="MGR")
    public Long getMgr() {
        return mgr;
    }

    public void setMgr(Long mgr) {
        this.mgr = mgr;
    }

    @Column(name="SAL")
    public Double getSal() {
        return sal;
    }

    public void setSal(Double sal) {
        this.sal = sal;
    }
}

　　4.创建 persistence.xml file 用来连接 Entities （或者 Domain Classes 和 POJOs） 和 database

    
        
        oracle.toplink.essentials.ejb.cmp3.EntityManagerFactoryProvider
        
        nl.amis.ejb30.hrm.Department
        nl.amis.ejb30.hrm.Employee
        
            
            
            
            
            
            
            
        
    

　　5.创建一个 Business Service class ，提供 Entitiy Services （好像一个out-of-container的Session Bean）

　　6.创建一个客户端

　　7.可以运行程序了

　　最后的包结构如下：

　　你体验过EJB3吗？发表下感想吧。

【责编:Amy】

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