分布式事务

1. TCC  基于RM本地事务来实现

   https://github.com/liuyangming/ByteTCC
   
   源码分析：
   1.1.1. Spring Cloud
   <dependency>
   	<groupId>org.bytesoft</groupId>
   	<artifactId>bytetcc-supports-springcloud</artifactId>
   	<version>0.5.7</version>
   </dependency>
   1.1.2. dubbo
   <dependency>
   	<groupId>org.bytesoft</groupId>
   	<artifactId>bytetcc-supports-dubbo</artifactId>
   	<version>0.5.7</version>
   </dependency>
   1.2 Compose a business service
   @Service("accountService")
   @Compensable(
     interfaceClass = IAccountService.class 
   , confirmableKey = "accountServiceConfirm"
   , cancellableKey = "accountServiceCancel"
   )
   public class AccountServiceImpl implements IAccountService {
   
   	@Resource(name = "jdbcTemplate")
   	private JdbcTemplate jdbcTemplate;
   
   	@Transactional
   	public void increaseAmount(String accountId, double amount) throws ServiceException {
   	    this.jdbcTemplate.update("update tb_account set frozen = frozen + ? where acct_id = ?", amount, acctId);
   	}
   
   }
   1.3 Compose a confirm service
   @Service("accountServiceConfirm")
   public class AccountServiceConfirm implements IAccountService {
   
   	@Resource(name = "jdbcTemplate")
   	private JdbcTemplate jdbcTemplate;
   
   	@Transactional
   	public void increaseAmount(String accountId, double amount) throws ServiceException {
   	    this.jdbcTemplate.update("update tb_account set amount = amount + ?, frozen = frozen - ? where acct_id = ?", amount, amount, acctId);
   	}
   
   }
   1.4 Compose a cancel service
   @Service("accountServiceCancel")
   public class AccountServiceCancel implements IAccountService {
   
   	@Resource(name = "jdbcTemplate")
   	private JdbcTemplate jdbcTemplate;
   
   	@Transactional
   	public void increaseAmount(String accountId, double amount) throws ServiceException {
   	    this.jdbcTemplate.update("update tb_account set frozen = frozen - ? where acct_id = ?", amount, acctId);
   	}
   
   }

2. sega