Java

Whether you are revising for interviews or sharpening your backend skills, this page gives you a structured view of important Java concepts. You will find articles on core language fundamentals, JVM and memory behavior, Java Streams, the Collections Framework, and multithreading patterns and APIs. Each link is designed to explain not just the “what” but also the “how” and “why” behind commonly used Java features.

Introduction to Java
  1. What is Java?
  2. Understanding Java Virtual Machine (JVM)
  3. Lifecycle of Memory in Java
Java Streams
  1. Java Streams - Intermediate Operations
  2. Java Streams - Terminal Operations
  3. Java Streams - Collector Operations
Collections Framework
  1. Java Collection Framework Hierarchy
  2. Internal Working of HashMap
  3. Internal working of ArrayList
  4. ArrayList vs LinkedList in Java
  5. ConcurrentHashMap vs Synchronized HashMap
Core Java Concepts
  1. Serialization in Java
  2. Understanding Marker Interfaces
  3. Serialization, Deserialization and Externalization in Java
Multithreading
  1. Threads in Java
  2. Understanding Multiple Threads
  3. ExecutorService, Future & CompletableFuture
  4. Modern Concurrency Utilities in Java
  5. Producer–Consumer Problem in Java Using BlockingQueue
  6. Fork/Join Framework in Java

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