Java Standard Edition (Java SE)
The core Java platform — language fundamentals, APIs, JVM, and JDK tools.
Java Database Libraries and Frameworks
JDBC, JPA/Hibernate, MyBatis, connection pools, and NoSQL clients.
Message Queues & Streaming
JMS, Apache Kafka, RabbitMQ, and message-driven architectures.
Spring Framework Family
Spring Core, Spring Boot, Spring Cloud, and Spring Data.
Java Security
JAAS, Apache Shiro, Spring Security, OAuth2, and JWT.
Build Tools
Maven, Gradle, and dependency management for Java projects.
Testing
Unit testing, mocking, and integration testing in Java.
Design Patterns
Classic design patterns with Java implementations.
Web Development
Servlet, JSP, REST APIs, and web application development.
Microservices
Microservice architecture, Dubbo, and gRPC.
Distributed Systems
Caching, distributed locks, and distributed transactions.
Performance & Tuning
JVM tuning, profiling, and application optimization.
Interview Guide
Java interview questions and system design topics.
Java Ecosystem
Popular libraries and frameworks beyond the JDK.
Algorithms & Data Structures
Sorting, searching, trees, graphs, and dynamic programming in Java.
Jakarta EE
Enterprise Java with Jakarta EE specifications.
Reactive Programming
Reactive streams and non-blocking Java.
DevOps for Java
CI/CD, containerization, and deployment automation.
Cloud Native Java
Deploying and running Java on cloud platforms.
Java Libraries
Popular open-source libraries for Java development.
Logging & Observability
Logging, metrics, and tracing for Java applications.
Code Quality
Static analysis, formatting, and refactoring.
Java Version Features
New language features from Java 8 through Java 21.