Do you know that? If a client is angry with you, do not respond immediately to them; give yourself a few minutes to cool-off. next

What is an object's lock and which object's have locks?

An object's lock is a mechanism that is used by multiple threads to obtain synchronized access to the object. A thread may execute a synchronized method of an object only after it has acquired the object's lock.

 

All objects and classes have locks. A class's lock is acquired on the class's Class object.