spring3+hibernate4+maven+junit 多库/多数据源实现

1.核心思想：

思路 写道

通过spring对多数据源的管理，在dao中动态的指定相对应的datasource。

2.动态指定数据源的方法约定：

约定 写道

不同库的dao放到对应的包下例：Master库中的dao的包路径是com.***.db.master.*。slave库的dao包的路径应是com.***.db.slave.***。

判定数据原方法 写道

判定dao类的路径是否包含master或者slave从而加载对应的数据源

3.实现代码

private void fixSession(){
	String name=this.getClass().getName();
	/**
	 * 如果是master 包下的dao 全部指定为 masterSessionFactory
	 */
	if(name.indexOf("com.xkorey.db.master")>-1){
	    sessionFactory = masterSessionFactory;
	}
	/**
	 * 默认的dao是 slaveSessionFactory 下的库
	 */
	else{
	    sessionFactory =  slaveSessionFactory;
	}
    }

4.这样实现的缺点，暂时还未想到。欢迎网友补充。

缺陷 写道

未知

5.开始贴代码，附件(hsm.zip)是eclipse下的项目工程包。
6.建库、表sql

--create database

-- master database
create database master character set `gbk` collate `gbk_chinese_ci`;
-- slave database
create database slave character set `gbk` collate `gbk_chinese_ci`;


-- create tables 
use master;
create table users(
id int not null auto_increment,
name varchar(20),
age int,
primary key(id)) ENGINE = INNODB,AUTO_INCREMENT=1000;

use slave;
create table user_info(
id int not null auto_increment,
uid int,
info varchar(20),
primary key(id)) ENGINE = INNODB,AUTO_INCREMENT=1000;


--insert data

use master;
insert into users(name,age) values('xkorey',28);
use slave;
insert into user_info(uid,info) values(1000,'hello xkorey.');

7.maven jar包依赖 pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>hsm</groupId>
  <artifactId>hsm</artifactId>
  <packaging>war</packaging>
  <version>0.0.1-SNAPSHOT</version>
  <name>hsm Maven Webapp</name>
  <url>http://maven.apache.org</url>
  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
    
    	<!-- spring  -->
    <dependency>
	 	<groupId>org.springframework</groupId>
	 	<artifactId>spring-context</artifactId>
	 	<version>3.2.3.RELEASE</version>
	</dependency> 
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-context-support</artifactId>
		<version>3.2.3.RELEASE</version>
	</dependency>
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-orm</artifactId>
		<version>3.2.3.RELEASE</version>
	</dependency>
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-webmvc</artifactId>
		<version>3.2.3.RELEASE</version>
	</dependency>
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-web</artifactId>
		<version>3.2.3.RELEASE</version>
	</dependency>
	<dependency>
		<groupId>org.springframework.security</groupId>
		<artifactId>spring-security-core</artifactId>
		<version>3.1.4.RELEASE</version>
	</dependency>
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-tx</artifactId>
		<version>3.2.3.RELEASE</version>
	</dependency>
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-test</artifactId>
		<version>3.2.1.RELEASE</version>
	</dependency>	
	<dependency>
		<groupId>org.aspectj</groupId>
		<artifactId>aspectjweaver</artifactId>
		<version>1.7.2</version>
	</dependency>
            
	            
            
            
	
	<!-- hibernate -->
	<dependency>
	<groupId>org.hibernate</groupId>
	<artifactId>hibernate-core</artifactId>
	<version>4.2.2.Final</version>
	</dependency>
	<dependency>
		<groupId>org.hibernate</groupId>
		<artifactId>hibernate-validator</artifactId>
		<version>4.2.0.Final</version>
	</dependency>
	            
            
	            
	            
	            
	
	<!-- mysql -->
	<dependency>
		<groupId>mysql</groupId>
		<artifactId>mysql-connector-java</artifactId>
		<version>5.1.25</version>
	</dependency>
    
    
  </dependencies>
  <build>
    <finalName>hsm</finalName>
  </build>
</project>

8.spring配置文件

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
       http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
       http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd
       ">
       
	<bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
	        <property name="locations">
	            <list>
	                <value>classpath:hsm-db-master.properties</value>
	                <value>classpath:hsm-db-slave.properties</value>
	            </list>
	        </property>
	</bean>
	
	<context:annotation-config />
	
	<context:component-scan base-package="com.xkorey.db" />
	
    <import resource="db-master.xml" /> 
    <import resource="db-slave.xml" />
    
    
    </beans>

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
       http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
       http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd
       ">
       
    <!-- Hibernate Data Source -->
    <bean id="masterDataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName"><value>${connection.master.driver_class}</value></property>
        <property name="url"><value>${connection.master.url}</value></property>
        <property name="username"><value>${connection.master.username}</value></property>
        <property name="password"><value>${connection.master.password}</value></property>
    </bean>    
     <!-- Hibernate Session Factory -->
    <bean id="masterSessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
        <property name="dataSource"><ref local="masterDataSource"/></property>
        <property name="packagesToScan" value="com.xkorey.db.master" />
        <property name="hibernateProperties">
        <props>
            <prop key="hibernate.dialect">${hibernate.master.dialect}</prop>
            <prop key="hibernate.show_sql">true</prop>
        </props>
        </property>
    </bean> 
    <!-- Transaction manager for a single Hibernate SessionFactory (alternative to JTA) HibernateTransactionManager -->
    <tx:annotation-driven transaction-manager="masterTransactionManager"/>
    <bean id="masterTransactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
        <property name="sessionFactory"><ref local="masterSessionFactory"/></property>
    </bean> 
</beans>

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
       http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
       http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd
       ">

    <!-- Hibernate Data Source -->
    <bean id="slaveDataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName"><value>${connection.slave.driver_class}</value></property>
        <property name="url"><value>${connection.slave.url}</value></property>
        <property name="username"><value>${connection.slave.username}</value></property>
        <property name="password"><value>${connection.slave.password}</value></property>
    </bean>    
     <!-- Hibernate Session Factory -->
    <bean id="slaveSessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
        <property name="dataSource"><ref local="slaveDataSource"/></property>
        <property name="packagesToScan" value="com.xkorey.db.slave" />
        <property name="hibernateProperties">
        <props>
            <prop key="hibernate.dialect">${hibernate.slave.dialect}</prop>
            <prop key="hibernate.show_sql">true</prop>
        </props>
        </property>
    </bean> 
    <!-- Transaction manager for a single Hibernate SessionFactory (alternative to JTA) HibernateTransactionManager -->
    <tx:annotation-driven transaction-manager="slaveTransactionManager"/>
    <bean id="slaveTransactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
        <property name="sessionFactory"><ref local="slaveSessionFactory"/></property>
    </bean>
</beans>

9.properties 配置文件

hibernate.master.dialect=org.hibernate.dialect.MySQLInnoDBDialect


connection.master.driver_class=com.mysql.jdbc.Driver
connection.master.url=jdbc:mysql://localhost:3306/master?useUnicode=true&characterEncoding=gbk
connection.master.username=root
connection.master.password=这里是你连库的密码

hibernate.slave.dialect=org.hibernate.dialect.MySQLInnoDBDialect


connection.slave.driver_class=com.mysql.jdbc.Driver
connection.slave.url=jdbc:mysql://localhost:3306/slave?useUnicode=true&characterEncoding=gbk
connection.slave.username=root
connection.slave.password=这里是你连库的密码

10.java 代码 略去 java bean 即spring中的model代码只贴 dao 。

父类dao

public class GenericDao<T extends java.io.Serializable> {

    	
    @Autowired
    @Qualifier("masterSessionFactory")
    private SessionFactory masterSessionFactory;
    
    
    @Autowired
    @Qualifier("slaveSessionFactory")
    private SessionFactory slaveSessionFactory;
    
    
    private SessionFactory sessionFactory;
    
    
    private void fixSession(){
	String name=this.getClass().getName();
	/**
	 * 如果是master 包下的dao 全部指定为 masterSessionFactory
	 */
	if(name.indexOf("com.xkorey.db.master")>-1){
	    sessionFactory = masterSessionFactory;
	}
	/**
	 * 默认的dao是 slaveSessionFactory 下的库
	 */
	else{
	    sessionFactory =  slaveSessionFactory;
	}
    }
    
    public Session getSession() {
	fixSession();
        return sessionFactory.getCurrentSession();
    }

注意UsersDao的包路径是 package com.xkorey.db.master.dao;

@Repository("UsersDao")
public class UsersDao extends GenericDao<Users>{
//根据网友建议其实也可以在dao中直接注入 sessionFactory 像这样
//  @Autowired
//  @Qualifier("masterSessionFactory")
//  private SessionFactory sessionFactory;
}

注意UserinfoDao的包路径是 package com.xkorey.db.slave.dao;

@Repository("UserinfoDao")
public class UserinfoDao extends GenericDao<Userinfo>{
// 根据网友建议实也可以在dao中直接注入 sessionFactory 像这样
//    @Autowired
//    @Qualifier("slaveSessionFactory")
//    private SessionFactory sessionFactory;
}

@Service("UsersService")
@Transactional(value="masterTransactionManager")
public class UsersService {
    
    @Autowired
    @Qualifier("UsersDao")
    private UsersDao usersDao;
    
    public int findUserAgeById(int id){
	Users users = (Users) usersDao.getSession().get(Users.class,id);
	return users.age;
    }
}

@Service("UserinfoService")
@Transactional(value="slaveTransactionManager")
public class UserinfoService {

    @Autowired
    @Qualifier("UserinfoDao")
    private UserinfoDao userinfoDao;
    
    public String findUserInfoById(int id){
	Userinfo userinfo = (Userinfo) userinfoDao.getSession().get(Userinfo.class,id);
	return userinfo.info;
    }
}

11.junit 测试类

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations={"classpath:spring-base.xml"})
public class TestDao {

    
    @Autowired
    @Qualifier("UsersService")
    private UsersService usersService;
    
    @Autowired
    @Qualifier("UserinfoService")
    private UserinfoService userinfoService;
    
    
    @Test
    public void testMutilDataSource(){
	int id=1000;
	System.out.println(usersService.findUserAgeById(id));
	System.out.println(userinfoService.findUserInfoById(id));
    }
    

}

测试类运行结果：

Hibernate: select users0_.id as id1_0_0_, users0_.age as age2_0_0_, users0_.name as name3_0_0_ from users users0_ where users0_.id=?
28
Hibernate: select userinfo0_.id as id1_0_0_, userinfo0_.info as info2_0_0_, userinfo0_.uid as uid3_0_0_ from user_info userinfo0_ where userinfo0_.id=?
hello xkorey.

截图：


12.最后贴张工程截图



13.项目环境
jdk7,eclipse Version: Kepler Release.maven:apache-maven-3.0.4

评论

5 楼 chenchunhuis 2015-06-10  

我们最近也在做这个事情，一楼的评论很有道理  

4 楼 mjs123 2015-03-11  

你好，我执行的时候 怎么老是报 No Session found for current thread 这个错误？

3 楼 youjianbo_han_87 2013-08-05  

追求技术 写道

你这是在提前已经知道了该使用哪个数据源的情况下使用多数据源，个人觉得完全没有必要再在代码里面通过class name来区别该使用哪个数据源。比如你把所有使用master数据源的dao都放到master包下面，既然你已经知道了某一dao是使用的master数据源，那么你完全可以在这个代码中直接注入一个master数据源对应的sessionFactory。

对的，对于读取的，全部从slave中读，插入和更新，都往主库里面操作。

2 楼 xkorey 2013-08-05  

追求技术 写道

你这是在提前已经知道了该使用哪个数据源的情况下使用多数据源，个人觉得完全没有必要再在代码里面通过class name来区别该使用哪个数据源。比如你把所有使用master数据源的dao都放到master包下面，既然你已经知道了某一dao是使用的master数据源，那么你完全可以在这个代码中直接注入一个master数据源对应的sessionFactory。

你说的有道理。这样做的话，那分包也就不用了。直接注入就可以了。

1 楼 追求技术 2013-08-05  

你这是在提前已经知道了该使用哪个数据源的情况下使用多数据源，个人觉得完全没有必要再在代码里面通过class name来区别该使用哪个数据源。比如你把所有使用master数据源的dao都放到master包下面，既然你已经知道了某一dao是使用的master数据源，那么你完全可以在这个代码中直接注入一个master数据源对应的sessionFactory。