Modern Concurrency Utilities in Java (java.util.concurrent)
Traditional multithreading in Java using Thread , Runnable , synchronized , and wait/notify works, but it becomes difficult to scale in modern backend applications. Java introduced the java.util.concurrent package to simplify concurrency, improve performance, and avoid common threading issues. 1. Why java.util.concurrent? Older threading models had several limitations: Manual thread creation → expensive & slow Risk of race conditions Complex synchronization No proper thread lifecycle management The concurrency framework solves these problems using: Thread pools Locks Atomic variables Coordination tools Asynchronous computation 2. ExecutorService (Thread Pooling) ExecutorService manages threads efficiently and avoids creating too many threads. ExecutorService service = Executors.newFixedThreadPool(5); service.submit(() -> System.out.println("Task executed")); Types of Executor Services: newSingleThreadExecutor() – ...