100+ Java Exercises (Simple, Intermediate & Complex)

Level Up Your Java Skills with Targeted Exercises – Master the Power of Java in This Ultimate Mega Pack!

What you'll learn
Solve over 100 exercises in C#
Deal with real programming problems
You will understand how to write high-performance Java code.
Crack Java job interviews easier
You will practice your skills by solving exercises in the browser,
Write OOP code easier with industry-standards and best practices like a Pro

Requirements
Basic Knowledge of Java
Willingness to Learn

Description
This course takes you on a journey from foundational Java programming to expert-level skills, equipping you to design efficient, scalable, and maintainable software. Through hands-on exercises, real-world scenarios, and best practices, you’ll gain practical expertise in:Java Core ConceptsObject-Oriented Programming (OOP)Classes, objects, and constructors.Method overriding and overloading.Inheritance, polymorphism, and encapsulation.Abstract classes and interfaces.GenericsImplementing generic data structures (e.g., LockFreeStack).Using bounded type parameters.Collections FrameworkUsing HashMap, LinkedHashMap, ConcurrentHashMap, Queue, and List.Working with thread-safe collections.Exception HandlingHandling checked and unchecked exceptions (IOException, InterruptedException, RuntimeException).Using try-catch-finally and custom exception messages.Concurrency and MultithreadingThread SafetySynchronization with synchronized blocks and methods.Thread-safe data structures like AtomicReference and ConcurrentHashMap.Advanced Concurrency MechanismsNon-blocking algorithms (e.g., LockFreeStack with Compare-And-Swap).Blocking queues with wait() and notifyAll().Executor FrameworkUsing ExecutorService, ScheduledExecutorService, and thread pools.Task scheduling with fixed-rate and fixed-delay jobs.Volatile and Atomicityvolatile for visibility across threads.Atomic operations with AtomicInteger and compareAndSet.Double-Checked LockingImplementing thread-safe singletons with minimal synchronization overhead.Data Structures and AlgorithmsCustom Data StructuresLRU Cache using LinkedHashMap.Lock-free stack with CAS.Thread-safe bounded blocking queues.Algorithmic PatternsImplementing Least Recently Used (LRU) cache eviction.Designing memory-efficient and high-performance ID generators (Snowflake-inspired).Advanced Design PatternsSingletonThread-safe Singleton with lazy initialization and double-checked locking.Publish-Subscribe (Pub/Sub)Implementing a messaging system with topics and subscribers.Dependency Injection (DI)Lightweight DI container for automatic dependency resolution.Event-Driven ArchitecturesCustom event loops for asynchronous task execution.Distributed SystemsDistributed ID GeneratorsTime-ordered unique IDs using timestamp, machine ID, and sequence numbers.Fault ToleranceImplementing Circuit Breaker patterns to handle service failures gracefully.Performance OptimizationLazy InitializationOptimizing resource creation to defer initialization until necessary.Non-Blocking SynchronizationUsing CAS for high-performance, lock-free data structures.Rate LimitingToken Bucket algorithm for throttling API requests.I/O and SerializationCustom Serialization FrameworkUsing reflection for object serialization and deserialization.File ProcessingMulti-threaded processing of large files with efficient chunking.Testing and DebuggingUnit TestingWriting JUnit 5 tests for validating implementation correctness.Testing thread safety and concurrency.Error HandlingGracefully managing system errors and preventing cascading failures.Real-World ApplicationsScalable CachesDesigning LRU caches for performance-critical applications.Distributed SystemsUnique ID generators for large-scale distributed applications.Circuit breakers for microservices.Task SchedulingImplementing schedulers for periodic and delayed tasks.Messaging SystemsPublish-Subscribe patterns for decoupled communication.Key Skills PracticedDesigning and implementing thread-safe systems.Understanding and applying advanced synchronization techniques.Building scalable, fault-tolerant, and performant solutions.Applying real-world design patterns and best practices.

Who this course is for
Aspiring Java developers seeking hands-on practice
Students preparing for Java programming interviews
Self-taught programmers looking to solidify Java fundamentals
Developers aiming to challenge and improve their Java skills
Anyone wanting a comprehensive exercise-based approach to mastering Java