java - JUnit 测试对 @transactional @Async 方法的调用导致超出锁等待超时

Question

我正在尝试测试异步运行的服务方法 (@Async)。

这是异步方法:

@Async
@Transactional(propagation=Propagation.SUPPORTS, isolation = Isolation.READ_UNCOMMITTED)
public Future<UserPrefs> checkLanguagePreference(long id) {

    UserPrefs prefs = prefsDao.retrieveUserPreferences(id);
    if(prefs == null || !StringUtils.hasLength(prefs.getLanguage())) {
        //Save a new sms-command object
        SmsBean command = SmsHelper.buildSmsCommand();
        if(! smsDao.checkSameCommandExists(id, command)) {

            smsDao.saveSms(id, new SmsBean[] {command}); //Will wait until Lock wait timeout
        }
    }
    return new AsyncResult<UserPrefs>(prefs);
}

这是调用异步方法的测试方法:

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(location = "...")
@TransactionConfiguration(transactionManager = "txManager", defaultRollback = false)
@Transactional(isolation = Isolation.READ_UNCOMMITTED)
@TestExecutionListeners( {  DependencyInjectionTestExecutionListener.class,
  DirtiesContextTestExecutionListener.class,
  TransactionalTestExecutionListener.class })
public class MessagingServiceTest {

   @Before
   public void setUp() {        
     //Avant tout mettre tout les sms en lu 
     smsDao.deleteAllSms(1);
     sessionFactory.getCurrentSession().flush();

     //On vérifie bien qu'il n y a plus de sms
     List<SmsBean> list = smsDao.getNewSmsList(1);
     assertEquals(0,list.size());
   }

   @Test
   public void checkLanguagePreferenceTest() throws InterruptedException, ExecutionException {
     User user = (User) sessionFactory.getCurrentSession().load(User.class, new Long(1));//idUser = 1
     // We explicitly blank the preference from db
     prefsDao.saveLanguagePref(new UserPrefs("",user));

     Future<UserPrefs> prefs =  messagingService.checkLanguagePreference(user.getId()); 
     System.out.println("wait completion of async task");           
     prefs.get();
     System.out.println("Async task has finished");
   }
}

当执行 prefs.get() 时，出现以下错误:

Caused by: org.springframework.orm.hibernate3.HibernateJdbcException: JDBC exception on Hibernate data access: SQLException for SQL [insert into SmsBean (destination, message, origin, sens, status, USER_ID) values (?, ?, ?, ?, ?, ?)]; SQL state [41000]; error code [1205]; could not insert:Caused by: java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1075)    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3562)    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3494)    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1960)    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2114)    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2696)    at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2105)    at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2398)    at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2316)    at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2301)    at org.apache.commons.dbcp.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:101)    at org.hibernate.id.IdentityGenerator$GetGeneratedKeysDelegate.executeAndExtract(IdentityGenerator.java:94)    at org.hibernate.id.insert.AbstractReturningDelegate.performInsert(AbstractReturningDelegate.java:57)    ... 39 more

发生这种情况是因为 setup 方法中的 smsDao.deleteAllSms 持有 SMS 表上的锁。

如何正确避免此锁定超时并能够成功运行我的测试？

感谢您的帮助。

仅供引用，这是一些控制台输出:

DEBUG - Adding transactional method 'checkLanguagePreferenceTest' with attribute: PROPAGATION_REQUIRED,ISOLATION_READ_COMMITTED; ''DEBUG - Explicit transaction definition [PROPAGATION_REQUIRED,ISOLATION_READ_COMMITTED; ''] found for test context [[TestContext@b76fa testClass = MessagingServiceTest, locations = array['file:src/main/resources/myapp-context.xml', 'file:src/main/resources/myapp-data.xml', 'file:src/main/resources/myapp-services.xml'], testInstance = fr.myapp.service.MessagingServiceTest@b01d43, testMethod = checkLanguagePreferenceTest@MessagingServiceTest, testException = [null]]]DEBUG - Retrieved @TransactionConfiguration [@org.springframework.test.context.transaction.Tran sactionConfiguration(defaultRollback=false, transactionManager=txManager)] for test class [class fr.myapp.service.MessagingServiceTest]DEBUG - Retrieved TransactionConfigurationAttributes [[TransactionConfigurationAttributes@5f7d3f transactionManagerName = 'txManager', defaultRollback = false]] for class [class fr.myapp.service.MessagingServiceTest]DEBUG - Returning cached instance of singleton bean 'txManager'DEBUG - Creating new transaction with name [checkLanguagePreferenceTest]: PROPAGATION_REQUIRED,ISOLATION_READ_COMMITTED; ''DEBUG - Opened new Session [org.hibernate.impl.SessionImpl@666a53] for Hibernate transactionDEBUG - Preparing JDBC Connection of Hibernate Session [org.hibernate.impl.SessionImpl@666a53]DEBUG - Changing isolation level of JDBC Connection [org.apache.commons.dbcp.PoolableConnection@1bde3d2] to 2DEBUG - Exposing Hibernate transaction as JDBC transaction [org.apache.commons.dbcp.PoolableConnection@1bde3d2]DEBUG - No method-level @Rollback override: using default rollback [false] for test context [[TestContext@b76fa testClass = MessagingServiceTest, locations = array['file:src/main/resources/myapp-context.xml', 'file:src/main/resources/myapp-data.xml', 'file:src/main/resources/myapp-services.xml'], testInstance = fr.myapp.service.MessagingServiceTest@b01d43, testMethod = checkLanguagePreferenceTest@MessagingServiceTest, testException = [null]]]INFO - Began transaction (1): transaction manager [org.springframework.orm.hibernate3.HibernateTransa ctionManager@17753a8]; rollback [false]Hibernate: delete from SmsBean where USER_ID=?Hibernate: select user0_.id as id3_1_, user0_.email as email3_1_, user0_.login as login3_1_, user0_.passwd as passwd3_1_, smsbeans1_.USER_ID as USER7_3_3_, smsbeans1_.id as id3_, smsbeans1_.id as id0_0_, smsbeans1_.destination as destinat2_0_0_, smsbeans1_.message as message0_0_, smsbeans1_.origin as origin0_0_, smsbeans1_.sens as sens0_0_, smsbeans1_.status as status0_0_, smsbeans1_.USER_ID as USER7_0_0_ from User user0_ left outer join SmsBean smsbeans1_ on user0_.id=smsbeans1_.USER_ID where user0_.id=?Hibernate: select user0_.id as id3_, user0_.email as email3_, user0_.login as login3_, user0_.passwd as passwd3_ from User user0_ where user0_.login=?Hibernate: select userprefs0_.id as id2_, userprefs0_.language as language2_, userprefs0_.USER_ID as USER3_2_ from user_prefs userprefs0_ where userprefs0_.USER_ID=?wait completion of async taskDEBUG - Returning cached instance of singleton bean 'txManager'INFO - Ener dans checkLanguagePreference(1)DEBUG - Opening Hibernate SessionDEBUG - Registering Spring transaction synchronization for new Hibernate SessionHibernate: select userprefs0_.id as id2_, userprefs0_.language as language2_, userprefs0_.USER_ID as USER3_2_ from user_prefs userprefs0_ where userprefs0_.USER_ID=?Hibernate: select user0_.id as id3_1_, user0_.email as email3_1_, user0_.login as login3_1_, user0_.passwd as passwd3_1_, smsbeans1_.USER_ID as USER7_3_3_, smsbeans1_.id as id3_, smsbeans1_.id as id0_0_, smsbeans1_.destination as destinat2_0_0_, smsbeans1_.message as message0_0_, smsbeans1_.origin as origin0_0_, smsbeans1_.sens as sens0_0_, smsbeans1_.status as status0_0_, smsbeans1_.USER_ID as USER7_0_0_ from User user0_ left outer join SmsBean smsbeans1_ on user0_.id=smsbeans1_.USER_ID where user0_.id=?INFO - Checking if same sms command already existHibernate: select * from smsbean S where S.USER_ID=? and S.status=? and S.message=?DEBUG - Flushing Hibernate Session on transaction synchronization//Deadlock here :Hibernate: insert into SmsBean (destination, message, origin, sens, status, USER_ID) values (?, ?, ?, ?, ?, ?)DEBUG - Closing Hibernate Session58799 [SimpleAsyncTaskExecutor-1] WARN org.hibernate.util.JDBCExceptionReporter - SQL Error: 1205, SQLState: 4100058799 [SimpleAsyncTaskExecutor-1] ERROR org.hibernate.util.JDBCExceptionReporter - Lock wait timeout exceeded; try restarting transaction

已解决，但仅供引用，我之前在 MySQL 论坛上创建过一个帖子，解释为什么我从 DBMS 的角度遇到了这个死锁。这是链接(也有很好的解释):

http://forums.mysql.com/read.php?97,409237,409237#msg-409237

Answer 1

由于您的测试被声明为 @Transactional，因此您有一项大事务分散在 setUp 方法和您的测试方法的执行中。该事务与异步操作中启动的另一个事务发生死锁(异步操作等待主事务获取的锁的释放，主事务等待异步操作的完成)。

您可以通过将主事务分解为多个单独的事务来解决此问题:

@Before
@Transactional // separate transaction for setUp
public void setUp() {        
    //Avant tout mettre tout les sms en lu 
    smsDao.deleteAllSms(1);
    sessionFactory.getCurrentSession().flush();

    //On vérifie bien qu'il n y a plus de sms
    List<SmsBean> list = smsDao.getNewSmsList(1);
    assertEquals(0,list.size());
}

@Test
@Transactional(propagation = NEVER) // Disable main transaction
public void checkLanguagePreferenceTest() throws InterruptedException, ExecutionException {

    // Programmatic transaction for test preparation
    User user = tx.execute(new TransactionCallback<User>() {
        public User doInTransaction(TransactionStatus status) {
            User user = (User) sessionFactory.getCurrentSession().load(User.class, new Long(1));//idUser = 1
            // We explicitly blank the preference from db
            prefsDao.saveLanguagePref(new UserPrefs("",user));    
            return user;
        }
    });

    Future<UserPrefs> prefs = messagingService.checkLanguagePreference(user.getId()); 
    System.out.println("wait completion of async task");            
    prefs.get();
    System.out.println("Async task has finished");
}

private TransactionTemplate tx;

@Autowired
public void setPtm(PlatformTransactionManager ptm) {
    tx = new TransactionTemplate(ptm);
}