This interface defines two methods that terminate a transactional output operation. These methods change the state of the transactional output stream to terminated. In the terminated state, invocations of these methods have no effect and invocations of output operations throw an IllegalStateException.

The terminating methods are commit() and abort(). The commit method must be called after the intended contents have been written to make the contents available, for example, as a new file. Otherwise, the abort method must be called, both to ensure that temporary resources are released and to ensure that a subsequent invocation of commit(), even by accident, has no effect.

The above description means that one may call commit() after calling abort() or call abort() after calling commit(); in either case, the second method invocation will have no effect. Thus, it is possible and convenient to call commit() at the end of a try body and call abort() in a finally clause of the same try statement. Even more conveniently, if the transactional writer is created and used within a try-with-resources statement, no explicit invocation of abort() is required, because it will be called implicitly (as close() is defined to call abort()).