基于JPA的Hibernate->CRUD(简单应用)

 

基于JPA的Hibernate->CRUD(简单应用)

 

原文地址

数据库用的是mysql5.0;
脚本如下:

use  test;
create   table  person
(
 id  int  AUTO_INCREMENT  primary   key ,
 username  varchar ( 20 ),
 password  varchar ( 20 )
);

insert   into  person  values ( null , ' ts ' , ' ts ' );

实体类用Annotation映射,代替hbm.

package  com.vo;

import  java.io.Serializable;

import  javax.persistence.Entity;
import  javax.persistence.GeneratedValue;
import  javax.persistence.GenerationType;
import  javax.persistence.Id;
import  javax.persistence.Table;

@SuppressWarnings( { "unchecked", "serial" } )
@Entity  // 标识是一个实体
@Table(name = " person " )  // 映射表
public   class  Person  implements  Serializable
{
    //主键映射
    @Id
    //主键自增
    @GeneratedValue(strategy=GenerationType.AUTO)
    private Integer id;
    //@Column(name="username"),对于列,可映射也可以不映射.注意保持列名和属性名一致就行 
    private String username;
    private String password;

    public Integer getId()
    {
        return id;
    }

    public void setId(Integer id)
    {
        this.id = id;
    }

    public String getUsername()
    {
        return username;
    }

    public void setUsername(String username)
    {
        this.username = username;
    }

    public String getPassword()
    {
        return password;
    }

    public void setPassword(String password)
    {
        this.password = password;
    }
}

hibernate.cfg.xml配置文件:

<? xml version="1.0" encoding="UTF-8" ?>
<! DOCTYPE hibernate-configuration PUBLIC
    "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
    "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd" >
< hibernate-configuration >
     < session-factory >
         < property  name ="dialect" > org.hibernate.dialect.MySQLDialect </ property >
         < property  name ="connection.driver_class" > com.mysql.jdbc.Driver </ property >
         < property  name ="connection.url" > jdbc:mysql://localhost:3306/test </ property >
         < property  name ="connection.username" > root </ property >
         < property  name ="connection.password" > root </ property >
         < property  name ="show_sql" > true </ property >
         <!--  实体类映射  -->
         < mapping  class ="com.vo.Person" />
     </ session-factory >
</ hibernate-configuration >     

测试类:

package  com.test;

import  java.util.List;

import  org.hibernate.Session;
import  org.hibernate.Transaction;
import  org.hibernate.cfg.AnnotationConfiguration;
import  org.junit.After;
import  org.junit.Before;
import  org.junit.Test;
import   static  org.junit.Assert. * ;
import  com.vo.Person;

public   class  PersonTest
{
    private Session session;
    private Transaction tx;

    @Before
    public void before()
    {
        session = new AnnotationConfiguration().configure()
                .buildSessionFactory().openSession();
        tx = session.getTransaction();
    }

    @After
    public void after()
    {
        session.close();
    }

    @Test
    public void testSave()
    {
        tx.begin();
        Person person = new Person();
        person.setUsername("zdw");
        person.setPassword("admin");
        session.save(person);
        tx.commit();
    }
    
    @Test
    public void testUpdate()
    {
        tx.begin();
        Person person = (Person) session.load(Person.class, 1);
        person.setPassword("test");
        session.update(person);
        tx.commit();
    }
    @SuppressWarnings("unchecked")
    @Test
    public void testQueryAll()
    {
        List<Person> persons = session.createCriteria(Person.class).list();
        assertNotNull(persons);
    }
    
    @Test
    public void testDelete()
    {
        Person person = (Person) session.load(Person.class, 1);
        session.delete(person);
    }
}