Java Concurrency Learning Note i

The less mutable states, the easier it is to ensure thread safety.
Try to declare the domain as the final type.
Immutable objects must be thread-safe and can reduce the complexity of concurrent programming, make it easier and secure to share publishing objects without using a synchronization mechanism.
Encapsulation helps to manage complexity and try not to publish variables, which are shared, as much as possible within objects or threads.
Protect each variable variable with a lock.
When you protect all variables in the same invariant condition, you need to use the same lock.
Hold the lock during the execution of the compliance operation.
Multi-threaded access to the same mutable variable requires a synchronization mechanism.

Java Concurrency Learning Note i