thread safe random access circular array in java?

Question

I need to cache the least recent result (say 10,000) of a concurrent system, and random access them. Since most of concurrent cache are based on linked list, I'm wondering if there is a thread safe random access circular array in java?

Answer 1

For caches without timeout, I often use the ConcurrentHashMap . You may also take a look at the CopyOnWriteArrayList .

https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ConcurrentHashMap.html https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/CopyOnWriteArrayList.html

Answer 2

There is an implementation of CircularFifoQueue in the Apache Commons Collections library. It contains a get() method for random access. For a thread-safe version, you can wrap its instance with the SynchronizedQueue wrapper. Another solution is the cyclic ArrayList/Vector implementation, described in detail here .