What are some of the improvements in Concurrency API in Java 8?

Java Multithreading - Interview Questions

Some important concurrent API enhancements are :

ConcurrentHashMap compute(), forEach(), forEachEntry(), forEachKey(), forEachValue(), merge(), reduce() and search() methods.

CompletableFuture that may be explicitly completed (setting its value and status).

Executors newWorkStealingPool() method to create a work-stealing thread pool using all available processors as its target parallelism level.