Java Interview Reference Guide – Collection Framework

A Collection represents a group of objects known as elements. Collection framework is basically group of interface with some specific implementation to manage elements of collection. Continue reading


Java Interview Reference Guide – Concurrent Framework

The Java Concurrent framework provide a powerful, extensible framework of high-performance threading utilities such as thread pools, Executors, synchronize, concurrent collection, locks, atomic variables and Fork/Join.

Concurrent framework consists below packages:

Java.util.concurrent: It is main package, which provides common libraries such as concurrent collection (ConcurrentHashMap.), ForkJoin, Executors, and Semaphore etc. to build concurrent application.

Java.util.concurrent.atomic: This subclass provide thread safe variable without synchronized key. It uses CAS (compare-and-set) instruction support to provide thread safe.

Java.util.concurrent.locks: This subclass contains low-level utility types for locking and waiting for conditions without using synchronization and monitors. Java.util.concurrent.locks.ReentrantLock implements Lock interface is more efficient over traditional synchronized based monitor lock mechanisms.

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