@Transactional的使用

异常代码

下面代码为了测试统一写在方法上

@GetMapping("testOne")@Transactional()public PTreeFolder testOne() {PTreeFolder insertData1=new PTreeFolder();String guid1=java.util.UUID.randomUUID().toString();insertData1.setFolderId(guid1);insertData1.setName("12");PTreeFolder p1= this.pTreeFolderService.insert(insertData1);PTreeFolder pData =this.pTreeFolderService.queryById(guid1);PTreeFolder insertData2=new PTreeFolder();String guid2=java.util.UUID.randomUUID().toString();//insertData2.setFolderId(guid2);insertData2.setName("12");PTreeFolder p2= this.pTreeFolderService.insert(insertData2);return p2;
}

断点调试

进异常

结果分析：

p1是正常数据，p2缺少主键，执行以后走了异常，数据pData是查询的值，注意异常之前是可以查询到的，这个时候数据库是不存储数据的（包括p1）。

执行完成以后报500，数据库存储了0条记录。

结果就是看到数据回滚了。

Catch如何处理

@GetMapping("testOne")@Transactional()public PTreeFolder testOne() {try {PTreeFolder insertData1=new PTreeFolder();String guid1=java.util.UUID.randomUUID().toString();insertData1.setFolderId(guid1);insertData1.setName("12");PTreeFolder p1= this.pTreeFolderService.insert(insertData1);PTreeFolder pData =this.pTreeFolderService.queryById(guid1);PTreeFolder insertData2=new PTreeFolder();String guid2=java.util.UUID.randomUUID().toString();//insertData2.setFolderId(guid2);insertData2.setName("12");PTreeFolder p2= this.pTreeFolderService.insert(insertData2);return p2;} catch (Exception e) {e.printStackTrace();return null;}}

执行以后

也就是说不会回滚。

分析

触发Transactional的回滚需要RunTimeException异常。

如果要在抛出非RuntimeException时也触发回滚机制，需要我们在注解上添加 rollbackFor = { Exception.class }属性。

@Transactional(rollbackFor = { Exception.class })

Try catch 以后异常被catch捕获不会触发Transactional的回滚。

解决

1、@ Transactional +catch中抛出RuntimeException异常

@GetMapping("testOne")@Transactional()public PTreeFolder testOne() {try {PTreeFolder insertData1=new PTreeFolder();String guid1=java.util.UUID.randomUUID().toString();insertData1.setFolderId(guid1);insertData1.setName("12");PTreeFolder p1= this.pTreeFolderService.insert(insertData1);PTreeFolder pData =this.pTreeFolderService.queryById(guid1);PTreeFolder insertData2=new PTreeFolder();String guid2=java.util.UUID.randomUUID().toString();//insertData2.setFolderId(guid2);insertData2.setName("12");PTreeFolder p2= this.pTreeFolderService.insert(insertData2);return p2;} catch (Exception e) {e.printStackTrace();throw  new RuntimeException();}
}

2、@Transactional(rollbackFor = { Exception.class }) 加上 catch中throw e

@GetMapping("testOne")@Transactional(rollbackFor = { Exception.class })public PTreeFolder testOne() {try {PTreeFolder insertData1=new PTreeFolder();String guid1=java.util.UUID.randomUUID().toString();insertData1.setFolderId(guid1);insertData1.setName("12");PTreeFolder p1= this.pTreeFolderService.insert(insertData1);PTreeFolder pData =this.pTreeFolderService.queryById(guid1);PTreeFolder insertData2=new PTreeFolder();String guid2=java.util.UUID.randomUUID().toString();//insertData2.setFolderId(guid2);insertData2.setName("12");PTreeFolder p2= this.pTreeFolderService.insert(insertData2);return p2;} catch (Exception e) {e.printStackTrace();throw e;}  }

3、直接回滚

TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();

代码

@GetMapping("testOne")@Transactional()public PTreeFolder testOne() {try {PTreeFolder insertData1 = new PTreeFolder();String guid1 = java.util.UUID.randomUUID().toString();insertData1.setFolderId(guid1);insertData1.setName("12");PTreeFolder p1 = this.pTreeFolderService.insert(insertData1);PTreeFolder pData = this.pTreeFolderService.queryById(guid1);PTreeFolder insertData2 = new PTreeFolder();String guid2 = java.util.UUID.randomUUID().toString();//insertData2.setFolderId(guid2);insertData2.setName("12");PTreeFolder p2 = this.pTreeFolderService.insert(insertData2);return p2;} catch (Exception e) {e.printStackTrace();TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();PTreeFolder resultData3 = new PTreeFolder();resultData3.setName("ddd");return resultData3;}}

推荐写法

@GetMapping("testOne")public PTreeFolder testOne() {return  this.pTreeFolderService.updateTest();
}

在Service中添加方法

@Transactional()@Overridepublic PTreeFolder updateTest(){try {PTreeFolder insertData1 = new PTreeFolder();String guid1 = java.util.UUID.randomUUID().toString();insertData1.setFolderId(guid1);insertData1.setName("12");PTreeFolder p1 = insert(insertData1);PTreeFolder pData = queryById(guid1);PTreeFolder insertData2 = new PTreeFolder();String guid2 = java.util.UUID.randomUUID().toString();//insertData2.setFolderId(guid2);insertData2.setName("12");PTreeFolder p2 = insert(insertData2);return p2;} catch (Exception e) {e.printStackTrace();TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();PTreeFolder resultData3 = new PTreeFolder();resultData3.setName("ddd");return resultData3;}}