WL
Java Full Stack Developer
Wassim Lagnaoui

Blog

Articles on Java, Spring Boot, DevOps, and building production systems.

Java Interview Questions (50 Q&A)

A curated list of essential Java questions with concise answers to prepare for interviews.

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Spring Boot REST API Best Practices

A practical guide to robust, evolvable REST APIs: resource modeling, validation, error handling, versioning, and security.

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Hibernate Essentials

An overview of Hibernate ORM: configuration, sessions, transactions, mappings, fetching, querying, caching, and performance.

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Spring Boot Concurrency Essentials

Async methods, executors, scheduling, thread pools, transactions, CompletableFuture, MVC vs WebFlux, synchronization, error handling, and Reactor.

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Why Java Streams Make Your Code Cleaner (and When They Don’t)

Readable transformations, fewer loops, and fewer bugs—plus the moments to stick with simple for-loops.

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The Biggest Mistake Developers Make with Spring Boot Security

Don’t trust the client or only the controller. Use layered authorization and safe defaults.

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