基于按annotation的hibernate主键生成策略

々上善若水々 — Wed, 23 Sep 2009 02:00:00 GMT

摘要: 这里讨论代理主键，业务主键（比如说复合键等）这里不讨论。一、JPA通用策略生成器通过annotation来映射hibernate实体的,基于annotation的hibernate主键标识为@Id, 其生成规则由@GeneratedValue设定的.这里的@id和@GeneratedValue都是JPA的标准用法, JPA提供四种标准用法,由@GeneratedValue的源代... 阅读全文

々上善若水々 2009-09-23 10:00 发表评论

Hibernate二级缓存详解

々上善若水々 — Tue, 04 Nov 2008 05:50:00 GMT

摘要: 与Session相对的是，SessionFactory也提供了相应的缓存机制。SessionFactory缓存可以依据功能和目的的不同而划分为内置缓存和外置缓存。 SessionFactory的内置缓存中存放了映射元数据和预定义SQL语句，映射元数据是映射文件中数据的副本，而预定义SQL语句是在 Hibernate初始化阶... 阅读全文

々上善若水々 2008-11-04 13:50 发表评论

基于JPA的CRUD(OneToMany)

々上善若水々 — Fri, 30 Nov 2007 07:42:00 GMT

摘要: 先建数据库: use test; create table person ( id int primary key AUTO_INCREMENT, username varchar(20) not null, password varchar(20) not&nb... 阅读全文

々上善若水々 2007-11-30 15:42 发表评论

基于JPA的Hibernate->CRUD(简单应用)(原创)

々上善若水々 — Thu, 29 Nov 2007 01:08:00 GMT

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.MySQLDialectproperty>
        <property name="connection.driver_class">com.mysql.jdbc.Driverproperty>
        <property name="connection.url">jdbc:mysql://localhost:3306/testproperty>
        <property name="connection.username">rootproperty>
        <property name="connection.password">rootproperty>
        <property name="show_sql">trueproperty>

        <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);
    }
}

经测试,增删改查全部正常.
这样的确很方便了.
源码可以在我的网盘下载. 点此下载

々上善若水々 2007-11-29 09:08 发表评论

BlogJava-我的漫漫程序之旅-文章分类-Hibernate

基于按annotation的hibernate主键生成策略

Hibernate二级缓存详解

基于JPA的CRUD(OneToMany)

基于JPA的Hibernate->CRUD(简单应用)(原创)