Spring 事务嵌套造成死锁 Lock wait timeout exceeded; try restarting transaction

数据库死锁Cause

nested exception is java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction

Spring 事务嵌套造成死锁。 
**解决方案:** 
当前调用事务的方法设置为 Propagation.SUPPORTS: 
@Transactional(propagation=Propagation.SUPPORTS)