Dao层系列-7-Hibernate Spring Data JPA

本篇完整代码可见：https://git.oschina.net/yaolifei/test/tree/master/test-hibernate-spring-data-jpa

Spring Data JPA又对代码做了一些精简，Dao如果没有复杂的逻辑，可以直接写一个接口继承自Spring Data JPA的相关接口就可以了，不需要实现。

applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns:context="http://www.springframework.org/schema/context"
	xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:jpa="http://www.springframework.org/schema/data/jpa"
	xsi:schemaLocation="
	http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
	http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd
	http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd
	http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa.xsd">
 
	<context:component-scan base-package="com.yaolifei.test" />
 	
	<context:property-placeholder location="jdbc.properties" />
	
	<bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" init-method="init" destroy-method="close"> 
		<property name="driverClassName" value="${jdbc.driverClassName}" /> 
		<property name="url" value="${jdbc.url}" /> 
		<property name="username" value= "${jdbc.username}" /> 
		<property name="password" value="${jdbc.password}" /> 
		<property name="maxActive" value="${jdbc.maxActive}" /> 
		<property name="validationQuery" value="${jdbc.validationQuery}" /> 
	</bean> 
	
	<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
		<property name="dataSource" ref="dataSource" />
		<property name="packagesToScan" value="com.yaolifei.test" />
		<property name="jpaVendorAdapter">
			<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" />
		</property>
		<property name="jpaProperties">
			<props>
				<prop key="hibernate.hbm2ddl.auto">update</prop>
				<prop key="hibernate.show_sql">true</prop>
				<prop key="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</prop>
			</props>
		</property>
	</bean>
 
	<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">  
		<property name="entityManagerFactory" ref="entityManagerFactory" />  
	</bean> 
	
	<jpa:repositories base-package="com.yaolifei.test.user.dao"
		entity-manager-factory-ref="entityManagerFactory" 
		transaction-manager-ref="transactionManager"/> 
        
	<tx:annotation-driven transaction-manager="transactionManager" />
	
	<bean class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor" />  

</beans>

UserDao.java

package com.yaolifei.test.user.dao;

import org.springframework.data.jpa.repository.JpaRepository;

import com.yaolifei.test.user.domain.User;

public interface UserDao extends JpaRepository<User, Integer> {
	
}

这么多就够了，UserDaoImpl已删除，稍微调整一下API就可以了