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Spring Boot: application contracts, data, and reliability

A complete Spring Boot framework course covering managed composition, HTTP, configuration, persistence, transactions, security, tests, caching, async work, observability, and reliable releases.

18 lessonsEnglish + ArabicContent reviewed
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In this course

Build a precise mental model of a Spring Boot application rather than collecting annotations. Eighteen developed lessons connect HTTP and dependency injection to typed configuration, validation, JPA, proxy-based transactions, security, testing, caching, asynchronous work, and operational reliability.

Examples use synthetic application contracts. Framework, build, configuration, test, HTTP, and deployment fragments are explicitly illustrative. Complete dependency-free Java models are validated separately so their limited evidence is not confused with running a Spring application. Each lesson includes diagnosis, worked exercises, takeaways, and official versioned references.

What you will learn

  • Explain Boot composition, dependency management, typed configuration, and servlet request handling.
  • Design explicit domain, persistence, transaction, and authorization contracts.
  • Choose tests that observe the actual framework boundary being claimed.
  • Reason about caches, executors, outbound calls, health, metrics, packaging, and outbox-based reliability.

Your learning path

Three levels

Basic: composition and HTTP contracts

Understand managed beans, typed settings, controller boundaries, validation, and explicit application policy.

  1. Boot runtime and a managed build
  2. Dependency injection and bean lifecycle
  3. External configuration and profiles
  4. HTTP controllers and response contracts
  5. Validation and safe problem details
  6. Application services and domain boundaries
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Intermediate: data, security, and framework evidence

Connect JPA, transaction proxies, authorization, focused tests, caches, and bounded asynchronous work.

  1. JPA repositories and persistence context
  2. Transaction proxies and error semantics
  3. Authentication, request rules, and object access
  4. Testing slices and evidence boundaries
  5. Caching keys and consistency
  6. Async work, scheduling, and event lifecycle
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Advanced: observability and resilient releases

Review health, performance, outbound calls, packaging, outbox workflows, and compatible API evolution.

  1. Actuator, health, and observability
  2. Performance, query shape, and capacity
  3. Outbound HTTP and resilience budgets
  4. Packaging, deployment, and graceful shutdown
  5. Reliable workflows and the outbox boundary
  6. API evolution and release evidence
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Who this is for

  • Java developers learning or maintaining servlet-style Spring Boot services.
  • Engineers reviewing framework boundaries, data integrity, access control, and release evidence.

Before you start

  • Comfort with Java17 classes, interfaces, records, exceptions, and collections.
  • Basic HTTP, JSON, and relational-data concepts.
  • No configured project, database account, credential, external service, or listener is required to read the examples.

Related technical solutions

Diagnose missing, ambiguous, and cyclic beansFind the failing composition boundary without widening scans, enabling every profile, or hiding dependency errors through broad overrides.Separate HTTP validation and security rejectionsLocate whether400,401,403,or404 came from routing, conversion, validation, authentication, authorization, or the selected disclosure policy.Diagnose missing transaction or rollback behaviorTrace the real managed call and transaction owner before changing propagation, swallowing errors, or assuming a repository call committed the intended unit.