Spring事务

前言

所谓编程式事务指的是通过编码方式实现事务，即类似于JDBC编程实现事务管理。管理使用TransactionTemplate或者直接使用底层的PlatformTransactionManager。对于编程式事务管理，spring推荐使用TransactionTemplate。

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案例

使用编程事务实现手动事务

@Component
public class TransactionUtils {

	@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 transactionStatus) {
		dataSourceTransactionManager.commit(transactionStatus);
	}

	// 回滚事务
	public void rollback(TransactionStatus transactionStatus) {
		dataSourceTransactionManager.rollback(transactionStatus);
	}
}

@Service
public class UserService {
	@Autowired
	private UserDao userDao;
	@Autowired
	private TransactionUtils transactionUtils;

	public void add() {
		TransactionStatus transactionStatus = null;
		try {
			transactionStatus = transactionUtils.begin();
			userDao.add("wangmazi", 27);
			int i = 1 / 0;
			System.out.println("我是add方法");
			userDao.add("zhangsan", 16);
			transactionUtils.commit(transactionStatus);
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			if (transactionStatus != null) {
				transactionStatus.rollbackToSavepoint(transactionStatus);
			}
		}

	}

}

AOP技术封装手动事务

@Component
@Aspect
public class AopTransaction {
	@Autowired
	private TransactionUtils transactionUtils;

	// // 异常通知
	@AfterThrowing("execution(* com.itmayiedu.service.UserService.add(..))")
	public void afterThrowing() {
		System.out.println("程序已经回滚");
		// 获取程序当前事务 进行回滚
		TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();
	}

	// 环绕通知
	@Around("execution(* com.itmayiedu.service.UserService.add(..))")
	public void around(ProceedingJoinPoint proceedingJoinPoint) throws Throwable {
		System.out.println("开启事务");
		TransactionStatus begin = transactionUtils.begin();
		proceedingJoinPoint.proceed();
		transactionUtils.commit(begin);
		System.out.println("提交事务");
	}

}

使用事务注意事项

事务是程序运行如果没有错误,会自动提交事物,如果程序运行发生异常,则会自动回滚。
如果使用了try捕获异常时.一定要在catch里面手动回滚。
事务手动回滚代码
TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();

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小结

感谢您的阅读~