spring PROPAGATION

Support a current transaction; create a new one if none exists.

支持一个当前事务;如果不存在，创建一个新的。

This is typically the default setting of a transaction definition, and typically defines a transaction synchronization scope.

默认设置，后面的不懂

Support a current transaction; execute non-transactionally if none exists.

支持当前事务；如果不存在当前事务则执行非事务。

Do not support a current transaction; rather always execute non-transactionally.

不执行当前事务；而是总是执行非事务

Create a new transaction, suspending the current transaction if one exists.

创建一个新的事务，如果存在当前事务的话暂停（挂起）当前事务。

Execute within a nested transaction if a current transaction exists

如果当前存在事务的话，执行一个嵌套的事务

Do not support a current transaction; throw an exception if a current transaction exists.

不支持当前事务；如果存在当前事务则抛出一个异常

Support a current transaction; throw an exception if no current transaction exists.

支持当前事务；如果不存在当前事务则抛出一个异常

巴特西