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Java Programming 128 posts

Core Java, Java 21 virtual threads, streams, lambdas, pattern matching, collections, and enterprise patterns.

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REST APIs, Spring Batch, Spring Security, JPA, microservices with Docker, Kafka, Redis, and unit testing.

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Mockito & Testing 9 articles → 1 Hub

The definitive Mockito guide — @Mock, @InjectMocks, Spy, ArgumentCaptor, @MockBean, void methods, and interview Q&A.

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ExecutorService, CompletableFuture, thread pools, shutdown strategies, invokeAll/invokeAny, virtual threads & Project Loom.

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Self joins, delete duplicates, concatenate rows, H2 troubleshooting, Spring Data JPA, and efficient data management.

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Microservices patterns, event-driven architecture with Kafka, scalable system design, API Gateway, and resilience patterns.

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SOLID Principles 6 posts

Single Responsibility, Open/Closed, Liskov Substitution, Interface Segregation, Dependency Inversion — with Java examples.

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The Complete Mockito Guide 2026

10 scattered Mockito articles → 1 authoritative hub. @Mock, @InjectMocks, stubbing, void methods, verify, ArgumentCaptor, @Spy, @MockBean, anti-patterns, and 10 interview Q&As with full answers. Code examples throughout.

@Mock & @InjectMocks when / thenReturn void methods verify() ArgumentCaptor @Spy @MockBean Interview Q&A
Open Mockito Hub →

9 articles • code examples • FAQ schema

🎯 Interview Preparation Hub

19 curated question banks — crack your next technical interview

☕ Java Exception Handling Interview

Expert answers to tricky exception handling questions

✨ Design Patterns Interview

Real-world design pattern questions with Java examples

⚡ Multithreading & Concurrency

Threads, locks, executors, CompletableFuture answers

🧪 Spring Boot Testing (JUnit/Mockito)

Unit testing, integration testing, mocking patterns

🧮 Sorting & Searching

With complexity analysis and Java implementations

🚀 System Design

Scalable notification system — architecture deep dive

🔐 Spring Security Interview

JWT, OAuth2, RBAC, CSRF, SecurityFilterChain questions

Popular Tutorials

Most-read articles from across all categories

Clean Code

SOLID Principles in Java with Real-World Examples

Applied SOLID patterns for improved code quality
Java 21

Virtual Threads — Project Loom Tutorial

Complete guide to virtual threads with working examples
Terraform

Terraform vs CloudFormation: Which is Better in 2026

Head-to-head comparison for infrastructure management
Spring Boot

Microservices Design Patterns with Spring Boot

Architecture patterns for scalable microservices
Java

Java Exception Handling — Complete Guide

Try-catch, custom exceptions, best practices
Clean Code

Mastering Clean Code Principles for Java Developers

Write readable, maintainable, and testable code

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