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在容器外使用EJB 3.0 Persistence

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

  該文介紹了如何在J2EE Container之外使用EJB 3.0 Persistence,實作了service類和data model. JAVA天堂

  Lucas Jellema提到的步驟如下:

  1.下載下傳和安裝 Java 5 (JDK 5.0/JRE 5.0)

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  2.下載下傳和配置 GlassFish

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  GlassFish:https://glassfish.dev.java.net/

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

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  比如其中的員工類:

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") JAVA天堂 
    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; 
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    }

    @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) { JAVA天堂 
        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.建立 persistence.xml file 用來連接配接 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.建立一個 Business Service class ,提供 Entitiy Services (好像一個out-of-container的Session Bean) JAVA天堂

  6.建立一個用戶端

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  7.可以運作程式了

  最後的包結構如下:

在容器外使用EJB 3.0 Persistence

  你體驗過EJB3嗎?發表下感想吧。