SpringBoot ThreadLocal 简单介绍及使用详解

public class ThreadLocalTest {
    private static ThreadLocal<String> localVar = new ThreadLocal<String>();
    static void print(String str) {
        // 打印当前线程中本地内存中变量的值
        System.out.println(str + ":" + localVar.get());
        // 清除内存中的本地变量
        localVar.remove();
    }
    public static void main(String[] args) throws InterruptedException {
        new Thread(new Runnable() {
            @Override
            public void run() {
                ThreadLocalTest.localVar.set("xdclass_A");
                print("A");
                // 打印本地变量
                System.out.println("清楚后：" + localVar.get());
            }
        }, "A").start();
        Thread.sleep(1000);
        new Thread(new Runnable() {
            @Override
            public void run() {
                ThreadLocalTest.localVar.set("xdclass_B");
                print("B");
                // 打印本地变量
                System.out.println("清楚后：" + localVar.get());
            }
        }, "B").start();
    }
}
A:xdclass_A
清楚后：null
B:xdclass_B
清楚后：null

@Slf4j
public class OnlineUserUtil {
    private final static ThreadLocal<UserInfo> threadLocal = new ThreadLocal<>();
    public static void set(UserInfo userInfo) {
        threadLocal.set(userInfo);
    }
    public static UserInfo get() {
        return threadLocal.get();
    }
    public static void remove() {
        threadLocal.remove();
    }
}

@Slf4j
@Aspect
@Component
@Order(2)
public class TokenAuthenticationAspect {
    @Before(value = "@annotation(tokenAuthentication)")
    public void doBefore(JoinPoint pjp, TokenAuthentication tokenAuthentication) {
        // 校验代码
        log.info("验证成功，保存到threadLocal userInfo={}", userInfo);
        OnlineUserUtil.set(userInfo);
    }
    @AfterReturning(value = "@annotation(tokenAuthentication)")
    public void doAfter(TokenAuthentication tokenAuthentication) {
        OnlineUserUtil.remove();
    }
}