Java Concurrency in Practice — JUC Deep Dive

This book provides a comprehensive, interview-oriented guide to Java concurrency and the java.util.concurrent (JUC) package. It covers everything from thread fundamentals and the Java Memory Model to lock internals, atomic operations, and advanced synchronizers.

Target audience: Senior Java backend engineers preparing for technical interviews, or anyone looking to deepen their understanding of JVM concurrency internals and distributed systems primitives.

Topics covered:

  • Thread lifecycle, daemon threads, and the monitor concept
  • CompletableFuture and asynchronous programming patterns
  • Lock taxonomy: optimistic vs. pessimistic, fair vs. unfair, reentrant, read-write
  • LockSupport, thread interruption, and the park/unpark mechanism
  • The Java Memory Model (JMM), happens-before, visibility, and ordering
  • volatile semantics and memory barriers
  • CAS (Compare-And-Swap) and the Unsafe class
  • Atomic classes: AtomicInteger, LongAdder, AtomicStampedReference, and more
  • ThreadLocal internals, weak references, and memory leak prevention
  • Java object memory layout: Mark Word, Klass Pointer, and alignment padding
  • synchronized internals and lock escalation (biased → lightweight → heavyweight)
  • AQS (AbstractQueuedSynchronizer) and the CLH queue
  • ReentrantLock, ReentrantReadWriteLock, and StampedLock