手动事务的几个类

主要的几个类

TransactionManager

PlatformTransactionManager

TransactionStatus

TransactionDefinition，TransactionTemplate

示例

@Service
public class MyService{
    
    @Autowired
    DataSourceTransactionManager transactionManager;
    
    public ResultMap lockStockWhenNewOrder(List<StockChangeByOrderDto> goodsModels) {
    
        //2.获取事务定义
        DefaultTransactionDefinition def = new DefaultTransactionDefinition();
        //3.设置事务隔离级别，开启新事务
        def.setPropagationBehavior(TransactionDefinition.PROPAGATION_REQUIRES_NEW);
        //4.获得事务状态，相当于开启事物
        TransactionStatus transactionStatus = transactionManager.getTransaction(def);
        try{
    
            //insert or update ...
            transactionManager.commit(transactionStatus);
        } catch (InterruptedException e) {
    
            transactionManager.rollback(transactionStatus);
        }
    }
}

创建一个控制事务的工具类，并交给spring管理

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.TransactionStatus;
import org.springframework.transaction.support.DefaultTransactionDefinition;

@Component
public class TransationUtils {
    

    @Autowired
    private PlatformTransactionManager platformTransactionManager;

    private TransactionStatus transactionStatus;

    /** * 开启事务 * * @return */
    public TransactionStatus beginTransaction() {
    
        transactionStatus = platformTransactionManager.getTransaction(new DefaultTransactionDefinition());
        return transactionStatus;
    }

    /** * 提交事务 */
    public void commitTransaction() {
    
        if (!transactionStatus.isCompleted()) {
    
            platformTransactionManager.commit(transactionStatus);
        }
    }

    /** * 回滚事务 */
    public void rollbackTransaction() {
    
        if (!transactionStatus.isCompleted()) {
    
            platformTransactionManager.rollback(transactionStatus);
        }
    }
}

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.stereotype.Component;
import org.springframework.transaction.TransactionStatus;
import org.springframework.transaction.interceptor.DefaultTransactionAttribute;
 
//编程事务（需要手动begin 手动回滚 手都提交）
@Component
public class TransactionUtils {
    
 
    // 获取事务源
    @Autowired
    private DataSourceTransactionManager dataSourceTransactionManager;
 
    // 开启事务
    public TransactionStatus begin() {
    
        TransactionStatus transaction = dataSourceTransactionManager.getTransaction(new DefaultTransactionAttribute());
        return transaction;
    }
 
    // 提交事务
    public void commit(TransactionStatus transaction) {
    
        dataSourceTransactionManager.commit(transaction);
    }
 
    // 回滚事务
    public void rollback(TransactionStatus transaction) {
    
        dataSourceTransactionManager.rollback(transaction);
    }
 
}

在需要使用到事务的类中注入该工具类,并使用

@Autowired
TransationUtils transationUtils;

public void test(){
    

	//开启事务
	transationUtils.beginTransaction();

	try {
    
		·············
		//操作成功提交事务
		transationUtils.commitTransaction();
	} catch (Exception e) {
    
		//捕获异常回滚事务
		transationUtils.rollbackTransaction();
		throw new RuntimeException("失败！");
	}
}

动开启事务的方法，原理就是在各种情况下判断事务有没有正常结束，如果捕获异常的话就回滚，正常的话就提交

注解事务 @Transactional

springboot 的话可以直接在方法上使用注释 @Transactional(rollbackFor = Exception.class)

自动开启事务，当出现异常时会自动回滚，但是如果使用 try catch 时事务会失效，需要手动回滚事务 ，具体操作如下

try {
    
      ······················
}catch (Exception e) {
    
   	//手动回滚
    TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();
}

参考

Spring 事务
手动事务及多线程事务