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Cannot get Guava 23's SimpleTimeLimiter example to compile


I'm following a combination of code that I see many times online, including examples here on SO, etc. but it just won't compile for me.

import com.google.common.util.concurrent.SimpleTimeLimiter;

import java.util.concurrent.Callable;
import java.util.concurrent.TimeUnit;

public class TimeLimit
{
    public static void main(String[] args)
    {
        SimpleTimeLimiter limiter = new SimpleTimeLimiter();
        String result = limiter.callWithTimeout(new Callable<String>()
        {
            public String call()
            {
                return longTimeExecutingMethod();
            }
        }, 3, TimeUnit.SECONDS, false);
    }

    public static String longTimeExecutingMethod()
    {
        return "long time executing method";
    }
}

The errors I'm getting are:

Error:(10, 45) java: constructor SimpleTimeLimiter in class com.google.common.util.concurrent.SimpleTimeLimiter cannot be applied to given types;
  required: java.util.concurrent.ExecutorService
  found: no arguments
  reason: actual and formal argument lists differ in length

And:

Error:(11, 40) java: method callWithTimeout in class com.google.common.util.concurrent.SimpleTimeLimiter cannot be applied to given types;
  required: java.util.concurrent.Callable<T>,long,java.util.concurrent.TimeUnit
  found: <anonymous java.util.concurrent.Callable<java.lang.String>>,int,java.util.concurrent.TimeUnit,boolean
  reason: cannot infer type-variable(s) T
    (actual and formal argument lists differ in length)

For the first Error I tried to create a Single Thread Executor:

SimpleTimeLimiter limiter = new SimpleTimeLimiter(Executors.newSingleThreadExecutor());

But that only resulted in changing the first compiler error with:

Error:(10, 45) java: SimpleTimeLimiter(java.util.concurrent.ExecutorService) has private access in com.google.common.util.concurrent.SimpleTimeLimiter

Solution

  • Use the static factory method:

    SimpleTimeLimiter limiter = SimpleTimeLimiter.create(executor);