Java
Concurrent Java code is notoriously difficult to test. The JVM's threading model, JIT compilation, and memory model create bugs that appear only under load, on specific hardware, or with particular GC settings. Good concurrent testing is a combination of the right synchronization primitives, stress testing, and race detection
Contract Testing
Spring Cloud Contract is the contract testing framework for Java Spring applications. Unlike Pact (which is consumer-driven), Spring Cloud Contract is provider-driven — the provider defines contracts in the Groovy DSL, generates WireMock stubs from them, and consumers use those stubs in their tests. This guide shows how to implement Spring
Testing
Testing REST APIs in Java has a reputation for being verbose. You set up an HTTP client, construct requests, execute them, parse the response, and then write assertions against the parsed data — often 20+ lines for a simple GET test. REST Assured changes this. It provides a fluent, BDD-style API
Testing
REST Assured's API was designed around the Given-When-Then structure from Behavior-Driven Development. This isn't just a cosmetic choice — tests written in BDD style are executable documentation. They describe what an API is supposed to do in terms that developers, QA engineers, and product managers can all
Testing
Spring Boot and REST Assured are a natural combination. Spring Boot makes building REST APIs fast; REST Assured makes testing them readable. The combination gives you a complete Java API testing stack that covers everything from controller unit tests to full integration tests against a running server. This guide covers
Testing
While JUnit is the default choice for most Java testing, TestNG offers compelling features for API test suites specifically. Test groups, flexible data providers, built-in parallel execution, and dependency management between tests make TestNG well-suited for organizing large API test collections. This guide covers using REST Assured with TestNG effectively.
Testing
Cucumber is one of the most widely adopted BDD frameworks, and Java remains its most popular language host. The combination gives teams a way to write tests in plain English that non-technical stakeholders can read while developers implement real automated browser and API tests underneath. This guide walks you through
Testing
Testing authenticated APIs is unavoidable in any real project. Most production endpoints require authentication — Basic Auth, Bearer tokens, OAuth2, or API keys. REST Assured provides built-in support for common authentication schemes and the flexibility to handle anything custom. This guide covers the patterns you'll actually use. Basic Authentication
Testing
JUnit and TestNG are the two dominant Java testing frameworks, and the choice between them comes up constantly on new projects. Both are mature, both are widely supported, and both can write the same test with nearly identical syntax. So how do you decide? Quick verdict: Choose JUnit 5 for
Testing
Spring Boot's testing support is one of its strongest features. Between JUnit 5, Mockito, AssertJ, and a suite of purpose-built test slice annotations, you get a layered testing strategy that lets you write fast unit tests, focused slice tests, and full integration tests — all within the same project.
Testing
Unit tests are supposed to test one thing in isolation. The moment your UserService needs a live database connection, a real email server, or a third-party HTTP client, your "unit" test becomes an integration test — slow, brittle, and hard to run in CI. Mockito solves this by letting
Testing
Unit testing is non-negotiable in professional Java development. JUnit is the framework that makes it practical — and it has been the standard Java testing tool for over two decades. This tutorial walks you through everything you need to write, organize, and run JUnit tests, from the first dependency declaration to