Use of thread variable threadlocal

We sometimes make multiple inquiries via token (pig: token is a key in Redis), such as:

Once in the login interceptor, once in the controller's business query, so there is a waste of performance and resources problems!!!

So how do you pass the data in the interceptor to the controller?

There are two types of scenarios:

1. Place the user object in the Request object

2, implemented with threadlocal thread variables (objects are in the same thread before entering Tomcat and generating a response)

Realize:

1, define a threadlocal related class

public class Userthreadlocal {
private static threadlocal<user> user_local = new threadlocal<> ();

Provide set and get methods externally
public static void SetUser (user user) {
User_local.set (user);
}
public static User GetUser () {
return User_local.get ();
}
}

2. Place the user object in the threadlocal in the login interceptor

Query to the user, put the user into threadlocal
Userthreadlocal.setuser (user);

3, the user can be obtained via threadlocal in the service

Get the user object from the threadlocal thread variable
User user = Userthreadlocal.getuser ();

Use of thread variable threadlocal