Threadlocal <t> class

Threadlocal <t> class
------- Each thread has only one t object
Key Methods:
T get (); // return the value in the current thread copy of the local variable of this thread
T initialvalue (); // return the "Initial Value" of the current thread of the local variable of this thread"
Void remove (); // remove the value of the current thread of the local variable of this thread
Void set (T value); // set the value in the current thread copy of the local variable of this thread to the specified value.

Principle: Use the threanlocal <t> class to bind each thread with its own connection. Modifying the connection of each thread will not affect the connection of other threads (equivalent to the copy mode)

threadlocal class