Spring & Transaction

  • 事务作用：在数据层保证一系列的数据库操作同成功同失败

  • Spring事务作用：在数据层或者业务层保障一系列的数据库操作同成功同失败

  • 接口：PlatfromTransactionManager

  • 实现类：DataSourceTransactionManager (底层是jdbc，和spring一样)

  • Spring 事务角色

    • 事务管理员：在业务层开启的事务，其它的事务都加入这个事务中，统一完成事务，做到了同成功同失败

    • 事务协调员：就是被加入的事务，指的是数据层的方法，也可以是业务层的方法。

config

package com.yang.config;
​
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.context.annotation.PropertySource;
import org.springframework.transaction.annotation.EnableTransactionManagement;
​
@Configuration
@ComponentScan("com.yang")
@PropertySource("jdbc.properties")
@Import({JdbcConfig.class,MybatisConfig.class})
@EnableTransactionManagement//开启事务
public class SpringConfig {
}

jdbcConfig

package com.yang.config;
​
import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;
​
import javax.sql.DataSource;
​
public class JdbcConfig {
    @Value("${jdbc.driver}")
    private String driver;
    @Value("${jdbc.url}")
    private String url;
    @Value("${jdbc.username}")
    private String username;
    @Value("${jdbc.password}")
    private String password;
​
    @Bean
    public DataSource dataSource(){
        DruidDataSource data = new DruidDataSource();
        data.setPassword(password);
        data.setUsername(username);
        data.setUrl(url);
        data.setDriverClassName(driver);
        return data;
    }
    @Bean
    public PlatformTransactionManager transactionManager(DataSource data){
        DataSourceTransactionManager dtm = new DataSourceTransactionManager();
        dtm.setDataSource(data);
        return dtm;
    }
}

service

package com.yang.service;
​
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;
​
@Transactional(propagation = Propagation.REQUIRES_NEW)//开启独立的新事务
public interface LogService {
    void log(String out,String in,double money);
}

 

package com.yang.service;
​
import org.springframework.transaction.annotation.Transactional;
​
import java.io.IOException;
​
//可以加方法上；也可以加接口上，表示所有的方法都开始起事务
@Transactional
public interface AccountService {
    //rollbackFor指定异常回滚，有的异常是不会回滚的，例IOException
    //rollbackFor = {IOException.class}
​
    void accountService(String outAccount,String inAccount ,double money) throws IOException;
}
​

AccountServiceImpl.java

package com.yang.service.Impl;
​
import com.yang.dao.AccountDao;
import com.yang.service.AccountService;
import com.yang.service.LogService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
​
import java.io.IOException;
​
@Service
public class AccountServiceImpl implements AccountService {
​
    @Autowired
    private AccountDao accountDao;
    @Autowired
    private LogService logService;
​
    @Override
    public void accountService(String out, String in, double money) throws IOException {
​
        try {
            accountDao.outAccount(out, money);
//            int i = 1 / 0;
//            if (true) {throw new IOException();}
            accountDao.inAccount(in, money);
        } finally {
            logService.log(out,in,money);
            System.out.println("我爱你");
        }
    }
}
​

test

package com.yang;
​
import com.yang.config.SpringConfig;
import com.yang.service.AccountService;
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 java.io.IOException;
​
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = SpringConfig.class)
public class TransactionTest {
    @Autowired
    private AccountService accountService;
    @Test
    public void account() throws IOException {
        accountService.accountService("Tom","Jack",100);
    }
}