easier to see example of this

TestTimeout.java

package test;

import org.junit.Assert;
import org.junit.Test;

import java.util.concurrent.Callable;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

public class TestTimeout {
  @Test
  public void testTimeout() throws Exception {
   try {
      ScheduledExecutorService executor = Executors.newScheduledThreadPool(2);
      final Future<Integer> handler = executor.submit(new Callable<Integer>() {
        @Override
        public Integer call() throws Exception {
          Thread.sleep(8000L);
          return 5;
        }
      });
      executor.schedule((Runnable) () -> handler.cancel(true),
          5000,
          TimeUnit.MILLISECONDS);
      handler.get();
    } catch (Exception e) {
      return;
    }
    Assert.fail("Should have timed out");
  }

  }
}