import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.FutureTask;

public class Future{
    public static class CallerTask implements Callable<String>{

        @Override
        public String call() throws Exception {
            // TODO Auto-generated method stub
            return "hello,dawn";
        }
        
    }


    public static void main(String[] args) {
        FutureTask<String> futureTask=new FutureTask<>(new CallerTask());

        new Thread(futureTask).start();

        try{
            String result=futureTask.get();
            System.out.println(result);
        }catch(Exception e){
            e.printStackTrace();
        }
    }

}