1、基於類級別的呼叫

（1）編寫介面類UserInfoService.java

public interface UserInfoService {
    String getUserName() throws InterruptedException;
}

（2）編寫對應的實現類UserInfoServiceImpl.java

public class UserInfoServiceImpl implements UserInfoService {

    @Override
    public String getUserName() throws InterruptedException {
        System.out.println("123");
        Thread.sleep(500);
        System.out.println("456");
        return "tim";
    }
}
 

(3) 測試程式碼

 public static void main(String[] args) {
        TimeLimiter timeLimiter = new SimpleTimeLimiter();
        UserInfoService userInfoService = new UserInfoServiceImpl();
        UserInfoService userInfoService1 = timeLimiter.newProxy(userInfoService, UserInfoService.class, 20, TimeUnit.MILLISECONDS);
        try {
            String userName = userInfoService1.getUserName();
            System.out.println("userName:" + userName);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
 

（4）綜合上述可以寫成更通用的

/**
 * @author chenjintian
 * @email [email protected]
 * @date 2018/9/29
 * Description:
 */
public class UserInfoServiceImpl implements UserInfoService {
    
    private static final TimeLimiter TIME_LIMITER = new SimpleTimeLimiter();
    // 設定為可配置
    private static final long TIME_OUT_DURATION = 200;
    
    private static UserInfoService userInfoServiceProxy;
    
    static {
        UserInfoService userInfoService = new UserInfoServiceImpl();
        userInfoServiceProxy = TIME_LIMITER.newProxy(userInfoService, UserInfoService.class, TIME_OUT_DURATION, TimeUnit.MILLISECONDS);
    }

    @Override
    public String getUserName(String info) throws InterruptedException {
        System.out.println("123");
        Thread.sleep(500);
        System.out.println("456");
        return info;
    }

    @Override
    public String getUserNameWithTimeout(String info) throws InterruptedException {
        return userInfoServiceProxy.getUserName(info);
    }

    @Override
    public String getSex(String txt) {
        return "";
    }

    @Override
    public String getSexWithTimeout(String txt) {
        return userInfoServiceProxy.getSex(txt);
    }


    public static void main(String[] args) throws InterruptedException {
        UserInfoService userInfoService = new UserInfoServiceImpl();
        String result = userInfoService.getUserNameWithTimeout("tim");
        System.out.println("result is:" + result);
    }

}
 

2、基於方法級別的呼叫

public class SimpleTimeLimiterDemo {

    public static void main(String[] args) {

        SimpleTimeLimiter simpleTimeLimiter = new SimpleTimeLimiter();
        final AtomicBoolean isInterrupted = new AtomicBoolean();

        Callable<String> task = new Callable<String>() {
            @Override
            public String call() throws Exception {
                isInterrupted.set(true);
                Thread.sleep(200);
                isInterrupted.set(false);
                return "success";
            }
        };

        try {
            String result = simpleTimeLimiter.callWithTimeout(task, 20, TimeUnit.MILLISECONDS, true);
            System.out.println(result);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

分析：

上述程式碼實現呼叫方法超時後會報錯。

檢視原始碼本質上，Google的SimpleTimeLimiter是對Executor的future的包裝。