In simple words a static synchronized method will lock the class instead of the object, and it will lock the class because the keyword static means: "class instead of instance". The keyword synchronized means that only one thread can access the method at a time.

Can a static method be Synchronised?

static methods can be synchronized. But you have one lock per class.

Is synchronized non static method?

Synchronization is the way used to protect access to resources that are accessed concurrently. A synchronized block of code can only be executed by one thread at a time. ... When synchronizing a non static method, the monitor belongs to the instance. When synchronizing on a static method , the monitor belongs to the class.