Spring学习——JDBC事务

一时失言乱红尘 2022-05-12 01:46 174阅读 0赞

**spring 事务 主要是指jdbc事务**

当一组事务执行完时,需要提交commit,才能在数据库中完成执行,  
当一组事务中的某个错误时候,需要撤销回滚rollback()

当SQL执行报错时候,调用rollback函数,commit操作取消
    当没有commit操作时候,数据库数据不会发生改变,rollback操作无效
    
    1、JdbcTemplate.query/update ->  
    2、PlatformTransactionManager.commit ->  
    3、PlatformTransactionManager.rollback
    
    1执行成功后,JdbcTemplate内数据对象发生改变,但数据库数据未发生改变
    2执行成功后,JdbcTemplate内数据提交到数据库,数据库数据发生改变
    3执行成功后,数据数据还原到commit之前

Beans.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" 
        xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans-3.0.xsd ">
    
       
       <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
          <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
          <property name="url" value="jdbc:mysql://localhost:3306/test"/>
          <property name="username" value="root"/>
          <property name="password" value=""/>
       </bean>
    	
    	
       	<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
          	<property name="dataSource"  ref="dataSource" />    
       	</bean>	
    	
    	
       	<bean id="userJdbcTemplate" class="com.spring.transaction.demo.UserJdbcTemplate" >
       		
       		<property name="dataSource"  ref="dataSource" /> 
       		<property name="transactionManager"  ref="transactionManager" />    
       	</bean>
       
       
    </beans>

核心配置类

package com.spring.transaction.demo;
    
    import java.util.ArrayList;
    import java.util.List;
    import java.util.Map;
    
    import javax.sql.DataSource;
    
    import org.springframework.dao.DataAccessException;
    import org.springframework.jdbc.core.JdbcTemplate;
    import org.springframework.transaction.PlatformTransactionManager;
    import org.springframework.transaction.TransactionDefinition;
    import org.springframework.transaction.TransactionStatus;
    import org.springframework.transaction.support.DefaultTransactionDefinition;
    
    public class UserJdbcTemplate{
    
    	private JdbcTemplate jdbcTemplate;
    	private DataSource dataSource;
    	private PlatformTransactionManager ptm;
    	
    	public void setDataSource(DataSource dataSource) {
    		this.dataSource = dataSource;
    		this.jdbcTemplate = new JdbcTemplate(dataSource);
    	}
    	
    	public void setTransactionManager(PlatformTransactionManager ptm){
    		this.ptm = ptm;
    	}
    	
    	public void update(int id){
    		TransactionDefinition def = new DefaultTransactionDefinition();
    		TransactionStatus status = ptm.getTransaction(def);
    		try {
    			String sql = "insert into user(id,username,password) values("+id+",'lg','123456')";
    			System.out.println("sql执行:"+sql);
    			jdbcTemplate.update(sql);
    			
    			sql = "insert into user(id,username,password) values("+(id-1)+",'zdj','123456')";
    			System.out.println("sql执行:"+sql);
    			jdbcTemplate.update(sql);
    			
    			sql = "update user set username='zh' where id = 2";
    			System.out.println("sql执行:"+sql);
    			jdbcTemplate.update(sql);
    			
    			ptm.commit(status);
    		} catch (DataAccessException e) {
    			System.out.println("回滚");
    			ptm.rollback(status);
    			e.printStackTrace();
    		}
    	}
    	
    	public List<UserPO> queryAll(){
    		String sql = "select * from user";
    		List<Map<String, Object>> mapList = jdbcTemplate.queryForList(sql);
    		List<UserPO> list = new ArrayList();
    		for (int i = 0; i < mapList.size(); i++) {
    			UserPO user = new UserPO();
    			user.setId((Integer)mapList.get(i).get("id"));
    			user.setUsername(mapList.get(i).get("username").toString());
    			user.setPassword(mapList.get(i).get("password").toString());
    			list.add(user);
    		}
    		return list;
    	}
    }

SpringMain

package com.spring.transaction.demo;
    
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    
    public class SpringMain {
    	public static void main(String[] args){
    		ApplicationContext context = new ClassPathXmlApplicationContext("Beans.xml");
    		UserJdbcTemplate ujt = (UserJdbcTemplate) context.getBean("userJdbcTemplate");
    		System.out.println("--------第一次查询数据库-----------");
    		System.out.println(ujt.queryAll().toString());
    		
    		System.out.println("---------正常执行-----------");
    		ujt.update(2);
    		System.out.println("--------第二次查询数据库-----------");
    		System.out.println(ujt.queryAll().toString());
    		
    		System.out.println("---------错误执行-----------");
    		ujt.update(3);
    		System.out.println("--------第二次查询数据库-----------");
    		System.out.println(ujt.queryAll().toString());
    		
    	}
    }