/*

* Copyright (C) 2007-2014, GoodData(R) Corporation. All rights reserved.

*/

package com.gooddata;

import java.util.concurrent.TimeUnit;

import static com.gooddata.Validate.notNull;

/**

* Represents the result retrieved by polling on the REST API.

*/

public final class FutureResult<T> {

private final AbstractService service;

private final PollHandler<?,T> handler;

/**

* Creates a new instance of the result to be eventually retrieved by polling on the REST API.<p>

* For internal usage by services employing polling.

*

* @param service this service

* @param handler poll handler

*/

public FutureResult(final AbstractService service, final PollHandler<?,T> handler) {

this.service = notNull(service, "service");

this.handler = notNull(handler, "handler");

}

/**

* Checks if the result is available

*

* @return true if so

* @throws GoodDataException when polling fails or the thread was interrupted

*/

public boolean isDone() {

return handler.isDone() || service.pollOnce(handler);

}

/**

* Wait for the result to be available and return it's value

*

* @return result value

* @throws GoodDataException when polling fails or the thread was interrupted

*/

public T get() {

return get(0, null);

}

/**

* Wait for the result to be available up to given time and return it's value

*

* @param timeout timeout value

* @param unit timeout unit

* @return result value

* @throws GoodDataException when polling fails, the timeout expires or the thread was interrupted

*/

public T get(final long timeout, final TimeUnit unit) {

if (handler.isDone()) {

return handler.getResult();

}

return service.poll(handler, timeout, unit);

}

/**

* Get URI used for polling

*

* @return URI string

*/

public String getPollingUri() {

return handler.getPollingUri();

}

}