Retry policy in CompletionService

I need to configure retry policy for calling an API via ExecutorCompletionService.

Sample Code:

public void func() throws Exception{
    ExecutorService executorService = Executors.newFixedThreadPool(5);
    CompletionService<String> completionService = new ExecutorCompletionService<String>(executorService);
    List<Future<String>> list = new ArrayList<Future<String>>();
    for(int i=0; i<10; i++) {
        AsyncTest asyncTest = new AsyncTest();
        Future<String> futureString = completionService.submit(asyncTest);
        list.add(futureString);
    }
    while (list.size() > 0) {
        Future<String> futureResponse = completionService.take();
        System.out.println(futureResponse.get());
        list.remove(futureResponse);
        }
    executorService.shutdown();
}
public class AsyncTest implements Callable<String> {
       public String call() throws Exception {
              //returns a response from api call
              //this is a network call and throws TimeoutException
       }
}

What's the best way to implement retry policy for TimeoutException thrown while calling the API?