java.util.concurrent

I am looking for a way of pausing a Thread. I started with affectively using a boolean flag (called 'paused'), and wrapping a check with a while loop (pause). Within the while loop there’s a Thread.wait() to block the execution. I’ve been looking at the AtomicBoolean , which seems to do the trick apart from it doesn’t block. Is there a alternative or extended version of AtomicBoolean that has a block method ? i.e. something like AtomicBoolean.getFalse() of AtomoicBoolean.get(false) ? They have a Blocking Queue, so a Blocking value. Current setup is : while (paused.get()) { synchronized (paused

I’m using the descendingIterator method on ConcurrentSkipListSet. I’ve just checked the documentation and noticed the following comment: ‘Ascending ordered views and their iterators are faster than descending ones.’ See https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ConcurrentSkipListSet.html#descendingIterator-- Unfortunately it doesn’t provide any more information on this. What kind of performance difference is there? is it significant? and why is there a performance difference? If you look at the Wikipedia page for Skip Lists you will see that they are effectively a

I've noticed that some of the commands in my application fail with Caused by: ! com.netflix.hystrix.exception.HystrixRuntimeException: GetAPICommand timed-out and no fallback available. out: ! at com.netflix.hystrix.HystrixCommand.getFallbackOrThrowException(HystrixCommand.java:1631) out: ! at com.netflix.hystrix.HystrixCommand.access$2000(HystrixCommand.java:97) out: ! at com.netflix.hystrix.HystrixCommand$TimeoutObservable$1$1.tick(HystrixCommand.java:1025) out: ! at com.netflix.hystrix.HystrixCommand$1.performBlockingGetWithTimeout(HystrixCommand.java:621) out: ! at com.netflix.hystrix

I have the folloing code in my android app: /** * callback executed after fetching the data. */ public void OnPointsFetch(ArrayList<Shop> result) { toggleLoader(false); this.shops = result; if(activeFilter == Constants.POINTS_FILTER_AVAILABLE){ for(Shop s : result){ if(s.getClientPoints().getPointsAvailable() == 0){ this.shops.remove(s); } } } else{ for(Shop s : result){ if(s.getClientPoints().getPointsSpent() == 0){ this.shops.remove(s); } } } ptsListAdapter.setCollection(this.shops); ptsListAdapter.setFilter(this.activeFilter); } This method is called on the result of an async task. I need

I've read the blog, but i'm not sure whether his conclusion is correct : http://www.javacodegeeks.com/2010/09/java-best-practices-queue-battle-and.html#ixzz1seaiSLwp He said : As you can see from the provided performance results LinkedBlockingQueue achieved the best combined (adding and removing elements) performance results and should be your number one candidate for implementing producer – consumer schenarios. I wonder that, doen't it faster if i don't use lock in my code ? So why the LinkedBlockingQueue is faster than the lock-free Queue(ConcurrentLinkedQueue) ? Thanks !

I'm dealing with some third-party library code that involves creating expensive objects and caching them in a Map . The existing implementation is something like lock.lock() try { Foo result = cache.get(key); if (result == null) { result = createFooExpensively(key); cache.put(key, result); } return result; } finally { lock.unlock(); } Obviously this is not the best design when Foos for different keys can be created independently. My current hack is to use a Map of Futures : lock.lock(); Future<Foo> future; try { future = allFutures.get(key); if (future == null) { future = executorService

As per my requirement, I have to execute some particular code after certain period of time. To do the same I have chose ScheduledExecutorService.scheduleWithFixedDelay(runnable, 0, 5, TimeUnit.SECONDS) and it's working fine for me. But according to my another requirement, the time mentioned in fixedDelay should be configurable at runtime. Means, currently total Delay is 5 seconds but latter if user want then can change the time into 60 seconds and in runtime fixedDelay will run after 60 seconds. Any help would be appreciable. Please see the code: static int i = 0; static