Spring+Hibernate框架下Mysql读写分离、主从数据库配置(上)

转载：http://lujia35.iteye.com/blog/969466

介绍下mysql数据库读写分离在spring,hibernate框架下的配置。 
1.mysql连接配置文件jdbc.properties 
master.*.*表示主数据库连接参数，负责增，删，改； 
slave.*.*表示从数据库连接参数，只负责读取； 

jdbc.properties

 

master.jdbc.driverClassName=com.mysql.jdbc.Driver
master.jdbc.url=********
master.jdbc.username=********
master.jdbc.password=********

slave.jdbc.driverClassName=com.mysql.jdbc.Driver
slave.jdbc.url=********
slave.jdbc.username=********
slave.jdbc.password=********

把**改成你所需的连接参数； 

2.配置AOP切面类 DataSourceAdvice.java 

import java.lang.reflect.Method;
import org.springframework.aop.AfterReturningAdvice;
import org.springframework.aop.MethodBeforeAdvice;
import org.springframework.aop.ThrowsAdvice;

import com.company.datasource.DataSourceSwitcher;

public class DataSourceAdvice implements MethodBeforeAdvice, AfterReturningAdvice, ThrowsAdvice {
    // service方法执行之前被调用
    public void before(Method method, Object[] args, Object target) throws Throwable {
        System.out.println("切入点: " + target.getClass().getName() + "类中" + method.getName() + "方法");
        if(method.getName().startsWith("add")
            || method.getName().startsWith("create")
            || method.getName().startsWith("save")
            || method.getName().startsWith("edit")
            || method.getName().startsWith("update")
            || method.getName().startsWith("delete")
            || method.getName().startsWith("remove")){
            System.out.println("切换到: master");
            DataSourceSwitcher.setMaster();
        }
        else  {
            System.out.println("切换到: slave");
            DataSourceSwitcher.setSlave();
        }
    }

    // service方法执行完之后被调用
    public void afterReturning(Object arg0, Method method, Object[] args, Object target) throws Throwable {
    }

    // 抛出Exception之后被调用
    public void afterThrowing(Method method, Object[] args, Object target, Exception ex) throws Throwable {
        DataSourceSwitcher.setSlave();
        System.out.println("出现异常,切换到: slave");
    }

}

数据源选择类 DataSourceSwitcher.java 

package com.company.datasource;
import org.springframework.util.Assert;

public class DataSourceSwitcher {
    @SuppressWarnings("rawtypes")
    private static final ThreadLocal contextHolder = new ThreadLocal();

    @SuppressWarnings("unchecked")
    public static void setDataSource(String dataSource) {
        Assert.notNull(dataSource, "dataSource cannot be null");
        contextHolder.set(dataSource);
    }

    public static void setMaster(){
        clearDataSource();
    }

    public static void setSlave() {
        setDataSource("slave");
    }

    public static String getDataSource() {
        return (String) contextHolder.get();
    }

    public static void clearDataSource() {
        contextHolder.remove();
    }
}

DynamicDataSource.java数据源动态切换类 

package com.company.datasource;

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

public class DynamicDataSource extends AbstractRoutingDataSource {

    @Override
    protected Object determineCurrentLookupKey() {
        return DataSourceSwitcher.getDataSource();
    }

}

下面配置spring applicationContext.xml文件 （Spring+Hibernate框架下Mysql读写分离、主从数据库配置(下)）