Myeclipse6.0实现JPA 创建

1.首先先创建一个JAVA项目，之后对其添入JPA（项目-->右键-->MyEclipse->Add JPA 功能） ；

2.一般JPA对Toplink的支持比对hibernate的支持好点，所以我们直接默认就好，-->next；

3.选择JPA配置的数据源，（Driver 、catalog\Schema..） -->Finish ;

4.选中其中的一个表，右键-->创建JPA 反向工程 ；（我创建了一个表MyUser里面有字段：id pk,name varchar(20),password varchar(20) 。）

5.先设置放置的路径，我放在一个jpaDaoTest包中，产生一个实体Bean并更改persistence.xml产生一个实体。persistence.xml：

<?xml version="1.0" encoding="UTF-8"?>

<persistence xmlns="http://java.sun.com/xml/ns/persistence"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://java.sun.com/xml/ns/persistence

http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd" version="1.0">

<persistence-unit name="jpaTestPU"

transaction-type="RESOURCE_LOCAL">

<provider>

oracle.toplink.essentials.PersistenceProvider

</provider>

<class>jpaDao.MyUser</class>

<class>jpaDaoTest.EisArea</class>

<properties>

<property name="toplink.jdbc.driver"

value="com.microsoft.jdbc.sqlserver.SQLServerDriver" />

<property name="toplink.jdbc.url"

value="jdbc:microsoft:sqlserver://210.51.168.147:1433;DatabaseName=www_souvi_com" />

<property name="toplink.jdbc.user" value="web1621510" />

<property name="toplink.jdbc.password" value="fhq2020" />

</properties>

</persistence-unit>

</persistence>

之后在勾选上 Java Data Access Generation创建接口和其实现方法。类型为Basic DAO默认即可。

6.Finish ;

MyUser.java

package jpaDao;

import javax.persistence.Column;

import javax.persistence.Entity;

import javax.persistence.Id;

import javax.persistence.Table;

import javax.persistence.GenerationType;

import javax.persistence.GeneratedValue;

/** *//**

* MyUser generated by MyEclipse Persistence Tools

*/

@Entity

@Table(catalog = "web1621510",schema = "www_souvi_com",name = "MyUser",uniqueConstraints = ...{})

public class MyUser implements java.io.Serializable ...{

// Fields

private Integer id;

private String name;

private String password;

// Constructors

/** *//** default constructor */

public MyUser() ...{

}

/** *//** minimal constructor */

public MyUser(Integer id) ...{

this.id = id;

}

/** *//** full constructor */

public MyUser(Integer id, String name, String password) ...{

this.id = id;

this.name = name;

this.password = password;

}

// Property accessors

@Id

@Column(name = "id", unique = true, nullable = false, insertable = true, updatable = true)

@GeneratedValue(strategy=GenerationType.IDENTITY)

public Integer getId() ...{

return this.id;

}

public void setId(Integer id) ...{

this.id = id;

}

@Column(name = "name", unique = false, nullable = true, insertable = true, updatable = true, length = 20)

public String getName() ...{

return this.name;

}

public void setName(String name) ...{

this.name = name;

}

@Column(name = "password", unique = false, nullable = true, insertable = true, updatable = true, length = 20)

public String getPassword() ...{

return this.password;

}

public void setPassword(String password) ...{

this.password = password;

}

}

IMyUserDAO.java

package jpaDao;

import java.util.List;

/** *//**

* Interface for MyUserDAO.

*

* @author MyEclipse Persistence Tools

*/

public interface IMyUserDAO ...{

public void save(MyUser transientInstance);

public void delete(MyUser persistentInstance);

public MyUser update(MyUser detachedInstance);

public MyUser findById(Integer id);

public List<MyUser> findByProperty(String propertyName, Object value);

public List<MyUser> findByName(Object name);

public List<MyUser> findByPassword(Object password);

public List<MyUser> findAll();

}

MyUserDAO.java

package jpaDao;

import java.util.List;

import java.util.logging.Level;

import javax.persistence.EntityManager;

/** *//**

* Data access object (DAO) for domain model class MyUser.

*

* @see jpaDao.MyUser

* @author MyEclipse Persistence Tools

*/

public class MyUserDAO implements IMyUserDAO ...{

// property constants

public static final String NAME = "name";

public static final String PASSWORD = "password";

private EntityManager getEntityManager() ...{

return EntityManagerHelper.getEntityManager();

}

public void save(MyUser transientInstance) ...{

EntityManagerHelper.log("saving MyUser instance", Level.INFO, null);

try ...{

getEntityManager().persist(transientInstance);

EntityManagerHelper.log("save successful", Level.INFO, null);

} catch (RuntimeException re) ...{

EntityManagerHelper.log("save failed", Level.SEVERE, re);

throw re;

}

}

public void delete(MyUser persistentInstance) ...{

EntityManagerHelper.log("deleting MyUser instance", Level.INFO, null);

try ...{

getEntityManager().remove(persistentInstance);

EntityManagerHelper.log("delete successful", Level.INFO, null);

} catch (RuntimeException re) ...{

EntityManagerHelper.log("delete failed", Level.SEVERE, re);

throw re;

}

}

public MyUser update(MyUser detachedInstance) ...{

EntityManagerHelper.log("updating MyUser instance", Level.INFO, null);

try ...{

MyUser result = getEntityManager().merge(detachedInstance);

EntityManagerHelper.log("update successful", Level.INFO, null);

return result;

} catch (RuntimeException re) ...{

EntityManagerHelper.log("update failed", Level.SEVERE, re);

throw re;

}

}

public MyUser findById(Integer id) ...{

EntityManagerHelper.log("finding MyUser instance with id: " + id,

Level.INFO, null);

try ...{

MyUser instance = getEntityManager().find(MyUser.class, id);

return instance;

} catch (RuntimeException re) ...{

EntityManagerHelper.log("find failed", Level.SEVERE, re);

throw re;

}

}

@SuppressWarnings("unchecked")

public List<MyUser> findByProperty(String propertyName, Object value) ...{

EntityManagerHelper.log("finding MyUser instance with property: "

+ propertyName + ", value: " + value, Level.INFO, null);

try ...{

String queryString = "select model from MyUser model where model."

+ propertyName + "= :propertyValue";

return getEntityManager().createQuery(queryString).setParameter(

"propertyValue", value).getResultList();

} catch (RuntimeException re) ...{

EntityManagerHelper.log("find by property name failed",

Level.SEVERE, re);

;

throw re;

}

}

public List<MyUser> findByName(Object name) ...{

return findByProperty(NAME, name);

}

public List<MyUser> findByPassword(Object password) ...{

return findByProperty(PASSWORD, password);

}

@SuppressWarnings("unchecked")

public List<MyUser> findAll() ...{

EntityManagerHelper.log("finding all MyUser instances", Level.INFO,

null);

try ...{

String queryString = "select model from MyUser model";

return getEntityManager().createQuery(queryString).getResultList();

} catch (RuntimeException re) ...{

EntityManagerHelper.log("find all failed", Level.SEVERE, re);

;

throw re;

}

}

}

现在我们写一个测试类吧，

import jpaDao.* ;

import java.util.*;

public class Test ...{

/** *//**

* @param args

*/

public static void main(String[] args) ...{

// 开始事务

EntityManagerHelper.beginTransaction();

// 创建DAO

MyUserDAO dao = new MyUserDAO();

// 创建对象

MyUser user = new MyUser() ;

user.setName("chenhao") ;

user.setPassword("password");

//保存对象

dao.save(user) ;

//事务提交

EntityManagerHelper.commit() ;

System.out.println("++++++++++++++++++++++++");

// 得到所有的数据并遍利

List<MyUser> result = dao.findAll() ;

for(MyUser o : result)...{

System.out.println("id = " + o.getId()) ;

System.out.println("name = " + o.getName()) ;

System.out.println("password = " + o.getPassword()) ;

}

}

}

console:

[TopLink Info]: 2008.04.01 12:26:29.484--ServerSession(26680060)--TopLink, version: Oracle TopLink Essentials - 2.0 (Build b40-rc (03/21/2007))

[TopLink Info]: 2008.04.01 12:27:08.437--ServerSession(26680060)--file:/D:/workspace/jpaTest/bin/-jpaTestPU login successful

2008-4-1 0:27:08 jpaDao.EntityManagerHelper log

信息: saving MyUser instance

2008-4-1 0:27:08 jpaDao.EntityManagerHelper log

信息: save successful

++++++++++++++++++++++++

2008-4-1 0:27:08 jpaDao.EntityManagerHelper log

信息: finding all MyUser instances

id = 1

name = chenhao

原文链接:http://hi.baidu.com/xfpsh/item/f393d3e54b6913098c3ea8c4