Do any methods have to be synchronized if there's only the main thread?

Question

Do I really need to synchronize any methods if I'm not creating any threads (exception is the main). If so, can someone give a reason why and provide some examples please.

Answer 1

If you don't create any threads of your own, then no, you should not need to use the synchronized keyword. That's assuming you're not writing J2EE servlets or filters, or a library that others (who are using multiple threads) can call.

Answer 2

在这种情况下，您不需要任何同步，同步是多个线程访问共享数据时。

Answer 3

Synchronized methods are used when you don't want two threads to operate on any synchronized method at one time. If the application is single threaded there is no point taking a lock and adding an overhead of synchronization.

Answer 4

No, you should not as it will affect your performance. Synchronization should not be used if you are doing all in one thread.