MySQL - 【明白原理】Spring声明式事物抓包 - 《开发笔记》

使用
- sql
- DataSource
例子
总结

使用

使用 SpringBoot 建立一个测试项目.

sql

create database test;
-- auto-generated definition
create table test_transaction
(
  id    int auto_increment
    primary key,
  name  varchar(16) default ''              not null,
  email varchar(24) default ''              not null,
  birth timestamp default CURRENT_TIMESTAMP not null
  on update CURRENT_TIMESTAMP
)
  engine = InnoDB;

DataSource

/**
 * @author chenshun00@gmail.com
 * @since 2019/5/4
 */
@Configuration
@EnableTransactionManagement(proxyTargetClass = true) // 开启事务
public class DataSourceConfig implements EnvironmentAware {
    private Environment environment;
    @Bean(initMethod = "init", destroyMethod = "close")
    public DataSource dataSource() {
        DruidDataSource druidDataSource = new DruidDataSource();
        druidDataSource.setUsername(this.environment.getProperty("spring.datasource.username"));
        druidDataSource.setPassword(this.environment.getProperty("spring.datasource.password"));
        druidDataSource.setUrl(this.environment.getProperty("spring.datasource.url"));
        druidDataSource.setDriverClassName(this.environment.getProperty("spring.datasource.driver-class-name"));
        druidDataSource.setDbType(this.environment.getProperty("spring.datasource.type"));
        druidDataSource.setInitialSize(Integer.parseInt(this.environment.getProperty("spring.datasource.initialSize")));
        druidDataSource.setMaxActive(Integer.parseInt(this.environment.getProperty("spring.datasource.maxActive")));
        druidDataSource.setMaxWait(Integer.parseInt(this.environment.getProperty("spring.datasource.maxWait")));
        druidDataSource.setValidationQuery(this.environment.getProperty("spring.datasource.validationQuery"));
        druidDataSource.setTestWhileIdle(Boolean.parseBoolean(this.environment.getProperty("spring.datasource.testWhileIdle")));
        druidDataSource.setTestOnBorrow(Boolean.parseBoolean(this.environment.getProperty("spring.datasource.testOnBorrow")));
        druidDataSource.setTestOnReturn(Boolean.parseBoolean(this.environment.getProperty("spring.datasource.testOnReturn")));
        return druidDataSource;
    }
    @Override
    public void setEnvironment(Environment environment) {
        this.environment = environment;
    }
}

例子

SQL语句使用 wireshark 抓取. 源代码地址: https://github.com/chenshun00/mysql-transaction/

checked异常回滚

NullPointException

RuntimeException…

   set autocommit = 0
   INSERT INTO test_transaction ( name,email,birth ) VALUES ( 'chenshun00','chenshun00@gmail.com','2019-05-04 14:20:37.209')
   rollback
   SET autocommit=1
   @Transactional
   public void testUncheckedExceptionRollback() {
       testTransactionDao.addTestTransaction(build());
       throw new NullPointerException("测试checked异常会滚");
   }

unchecked异常不回滚

SQLException

other exception…

   set autocommit = 0
   INSERT INTO test_transaction ( name,email,birth ) VALUES ( 'chenshun00','chenshun00@gmail.com','2019-05-04 14:20:37.209' )
   SET autocommit=1
   @Transactional
   public void testCheckedException() throws SQLException {
       testTransactionDao.addTestTransaction(build());
       throw new SQLException("ggg");
   }

指定异常回滚

@Transactional(rollbackFor = {SQLException.class})

        set autocommit = 0
        INSERT INTO test_transaction ( name,email,birth ) VALUES ( 'chenshun00','chenshun00@gmail.com','2019-05-04 14:20:37.209' )
        rollback
        SET autocommit=1
        @Transactional(rollbackFor = {SQLException.class})
        public void testCheckedExceptionRollback() throws SQLException {
            testTransactionDao.addTestTransaction(build());
            throw new SQLException("ggg");
        }

嵌套方法(无异常)

      --nest method 共插入2条记录 sql
      SET autocommit=0
      select @@session.tx_read_only
      INSERT INTO test_transaction ( name,email,birth ) VALUES ( 'chenshun00','chenshun00@gmail.com','2019-05-04 14:47:00.572' )
      select @@session.tx_read_only
      INSERT INTO test_transaction ( name,email,birth ) VALUES ( 'chenshun00','chenshun00@gmail.com','2019-05-04 14:47:00.635' )
      commit
      SET autocommit=1
      @Transactional
      public void testNestMethod() {
          //insert
          testTransactionDao.addTestTransaction(build());
          this.subMethod();
      }
      private void subMethod() {
          testTransactionDao.addTestTransaction(build());
      }

嵌套方法带checked异常

      --子方法出现运行运行时异常，回滚
      SET autocommit=0
      select @@session.tx_read_only
      SELECT @@session.tx_isolation
      INSERT INTO test_transaction ( name,email,birth ) VALUES ( 'chenshun00','chenshun00@gmail.com','2019-05-04 14:57:47.05' )
      INSERT INTO test_transaction ( name,email,birth ) VALUES ( 'chenshun00','chenshun00@gmail.com','2019-05-04 14:57:47.141' )
      rollback
      SET autocommit=1
      @Transactional
      public void testNestMethodRuntimeException() {
          testTransactionDao.addTestTransaction(build());
          this.subExceptionMethod();
      }
      private void subExceptionMethod() {
          testTransactionDao.addTestTransaction(build());
          throw new NullPointerException("运行时异常测试");
      }

嵌套方法带unchecked异常.

      set autocommit = 1
      select @@session.tx_read_only
      SELECT @@session.tx_isolation
      set autocommit = 0
      insert sql语句
      insert sql语句
      commit
      set autocommit = 1
      @Transactional
      public void testNestMethodUncheckException() throws SQLException {
          testTransactionDao.addTestTransaction(build());
          this.subUncheckExceptionMethod();
      }
      private void subUncheckExceptionMethod() throws SQLException {
          testTransactionDao.addTestTransaction(build());
          throw new SQLException("运行时异常测试");
      }

嵌套方法指定异常回滚

      set autocommit = 1
      select @@session.tx_read_only
      SELECT @@session.tx_isolation
      set autocommit = 0
      insert sql语句
      insert sql语句
      rollback
      set autocommit = 1
      @Transactional(rollbackFor = {SQLException.class})
      public void testNestMethodUncheckExceptionRollback() throws SQLException {
          testTransactionDao.addTestTransaction(build());
          this.subUncheckExceptionMethodRollback();
      }
      private void subUncheckExceptionMethodRollback() throws SQLException {
          testTransactionDao.addTestTransaction(build());
          throw new SQLException("运行时异常测试");
      }

this 调用无事务

  /**
   * 测试调用未开启事务，直接是一条sql一个事务提交
   * 没有事务原因:没有Transactional注解，没有进入proxy代理当中，没有进入代码当中就进入不了事务,
   * this调用还是没有事务，这里如果要产生事务就需要获取当前(this)对象当proxy对象，再进行方法调用会产生事务
   */
  public void testMainMethodNoTransactionRuntimeException() {
      this.subMethodTransactionRuntimeException();
  }
  @Transactional
  public void subMethodTransactionRuntimeException() {
      testTransactionDao.addTestTransaction(build());
      throw new NullPointerException("11");
  }

this 调用带事务

  /**
   * proxy代理调用产生事务
   * 需要配置 @EnableAspectJAutoProxy(proxyTargetClass = true, exposeProxy = true)
   */
  public void testProxyObjectGetTransaction() throws SQLException {
      ((TestTransactionService) AopContext.currentProxy()).testProxyObjectGetTransactionSubMethod();
  }
  @Transactional(rollbackFor = {SQLException.class})
  public void testProxyObjectGetTransactionSubMethod() throws SQLException {
      testTransactionDao.addTestTransaction(build());
      throw new SQLException("11");
  }

多Transactional注解

  /**
   * 事务1
   * <p>
   * set autocommit = 0
   * insert
   * insert
   * commit
   * set autocommit = 1
   */
  @Transactional
  public void firstTransaction() {
      testTransactionDao.addTestTransaction(build());
      this.secondTransaction();
  }
  /**
   * 事务2
   */
  @Transactional
  public void secondTransaction() {
      testTransactionDao.addTestTransaction(build());
  }

总结

自己多试试，抓包看本质.