spring配置多数据源

基于spring来配置和使用多数据源还是比较简单的，因为spring框架已经预留了这样的接口可以方便数据源的切换。

DynamicDataSource类

package com.demo.core;

import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;

public class DynamicDataSource extends AbstractRoutingDataSource {

    @Override
    protected Object determineCurrentLookupKey() {
        // 从自定义的位置获取数据源标识
        return DynamicDataSourceHolder.getDataSource();
    }
}

DynamicDataSourceHolder类

package com.demo.core;

public class DynamicDataSourceHolder {
    /**
     * 注意：数据源标识保存在线程变量中，避免多线程操作数据源时互相干扰
     */
    private static final ThreadLocal THREAD_DATA_SOURCE = new ThreadLocal();
    
    public static String getDataSource() {
        return THREAD_DATA_SOURCE.get();
    }
    public static void setDataSource(String dataSource) {
        THREAD_DATA_SOURCE.set(dataSource);
    }
    public static void clearDataSource() {
        THREAD_DATA_SOURCE.remove();
    }
}

注解

package com.demo.core;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@Target({ ElementType.TYPE,ElementType.METHOD })
@Retention(RetentionPolicy.RUNTIME)
public @interface DataSource {

	String value();
}

切面

package com.demo.core;

import java.lang.reflect.Method;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.reflect.MethodSignature;

public class DataSourceAspect {

    /**
     * 拦截目标方法，获取由@DataSource指定的数据源标识，设置到线程存储中以便切换数据源
     * 
     * @param point
     * @throws Exception
     */
    public void intercept(JoinPoint point) throws Exception {
        Class target = point.getTarget().getClass();
        MethodSignature signature = (MethodSignature) point.getSignature();
        // 默认使用目标类型的注解，如果没有则使用其实现接口的注解
        for (Class clazz : target.getInterfaces()) {
            resolveDataSource(clazz, signature.getMethod());
        }
        resolveDataSource(target, signature.getMethod());
    }

    /**
     * 提取目标对象方法注解和类型注解中的数据源标识
     * 
     * @param clazz
     * @param method
     */
    private void resolveDataSource(Class clazz, Method method) {
        try {
            Class[] types = method.getParameterTypes();
            // 默认使用类型注解
            if (clazz.isAnnotationPresent(DataSource.class)) {
                DataSource source = clazz.getAnnotation(DataSource.class);
                DynamicDataSourceHolder.setDataSource(source.value());
            }
            // 方法注解可以覆盖类型注解
            Method m = clazz.getMethod(method.getName(), types);
            if (m != null && m.isAnnotationPresent(DataSource.class)) {
                DataSource source = m.getAnnotation(DataSource.class);
                DynamicDataSourceHolder.setDataSource(source.value());
            }
        } catch (Exception e) {
            System.out.println(clazz + ":" + e.getMessage());
        }
    }

}

service类

package com.demo.service.impl;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Service;

import com.demo.core.DataSource;
import com.demo.core.DynamicDataSourceHolder;
import com.demo.dao.UserDAO;
import com.demo.model.User;
import com.demo.service.UserService;

@Service
public class UserServiceImpl implements UserService{
 
    @Autowired
    @Qualifier("userDAO")
    private UserDAO userDAO;    
     
    public int insertUser(User user) {
    	return userDAO.insertUser(user);
    }

    public User queryUserById(String id) {
        return userDAO.queryUserByID(id);
    }
    
    @DataSource("dataSource1")//通过元注解 利用切面运行时自动设置数据源
    public User queryUserByIdDB2(String id) {
    	//DynamicDataSourceHolder.setDataSource("dataSource2"); 
    	//手动设置数据源
        return userDAO.queryUserByID(id);
    }
}

dao类

package com.demo.dao;

import org.springframework.stereotype.Repository;

import com.demo.model.User;
@Repository
public interface UserDAO {
	
	public int insertUser(User user);
	
	public User queryUserByID(String id);
}

单元测试service

package test.service;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import com.demo.service.UserService;

@RunWith(SpringJUnit4ClassRunner.class)  
@ContextConfiguration(locations={"/conf/spring-mybatis.xml"}) //加载配置文件
public class userServiceTest{
	
	@Autowired
	private UserService userservice;	
	@Test
	public void testuserService(){
//		System.err.println(userservice.queryUserById("1"));
		System.err.println(userservice.queryUserByIdDB2("1"));
	}
}

控制台输出

User [id=1, name=数据源1, password=admin1]

User [id=1, name=数据源2, password=admin2]

配置文件

转载 http://www.cnblogs.com/liujiduo/p/5004691.html  基于注解的Spring多数据源配置和使用 推荐

转载 http://blog.csdn.net/wangpeng047/article/details/8866239/ spring多数据源配置

转载 http://download.csdn.net/download/npf_java/8786825 多数据源事务控制