Apply timeout control around Java operation

Question

I\'m using a third party Java library to interact with a REST API. The REST API can sometimes take a long time to respond, eventually resulting in a java.net.ConnectExcept

Answer 1

This is probably the current way how this should be done with plain Java:

public String getResult(final RESTService restService, String url) throws TimeoutException {
    // should be a field, not a local variable
    ExecutorService threadPool = Executors.newCachedThreadPool();

    // Java 8:
    Callable callable = () -> restService.getResult(url);

    // Java 7:
    // Callable callable = new Callable() {
    //     @Override
    //     public String call() throws Exception {
    //         return restService.getResult(url);
    //     }
    // };

    Future future = threadPool.submit(callable);
    try {
        // throws a TimeoutException after 1000 ms
        return future.get(1000, TimeUnit.MILLISECONDS);
    } catch (ExecutionException e) {
        throw new RuntimeException(e.getCause());
    } catch (InterruptedException e) {
        Thread.currentThread().interrupt();
        throw new TimeoutException();
    }
}