Hands-on Application Development using Spring Boot (Shagun Bakliwal)（Z-Library）

【One-Line Pitch】 A practical, build-along guide that takes Java developers from a first Spring Boot project to a secured, documented, tested, cloud-deployed microservice. Best for developers who know some Java and want a single walkthrough of the framework's production features rather than a reference manual. 【Book Arc】 - **Opening (~0%–10%)**: Sets up the toolchain and mental model — JDK, Maven/Gradle, Spring Tool Suite, and how a Spring Boot project is generated and built. Solves the "where do I even start" problem before any code is written. - **Early (~10%–33%)**: Dives into configuration and the annotation layer: starter dependencies, auto-configuration and conditional beans, and the core Spring/Spring Boot annotations (wiring, lazy init, async, scheduling, profiles). This is the conceptual backbone the rest of the book leans on. - **Middle (~33%–52%)**: Moves into data and APIs — JdbcTemplate and Spring Data JPA against H2 then MySQL, query methods, caching, and building RESTful endpoints with validation and centralized error handling via controller advice. - **Late (~52%–70%)**: Adds the distributed-systems layer: service discovery with Eureka, inter-service calls via RestTemplate, externalized configuration and profiles, and the API gateway for request routing. - **Late (~70%–85%)**: Hardens the application — authentication/authorization with Spring Security filters and OAuth 2.0, client-side load balancing, and circuit breakers to contain cascading failures under high traffic. - **Ending (~85%–100%)**: Operationalizes it — Logback logging plus Zipkin/Sleuth tracing and the ELK stack, Swagger API documentation with DTO generation from YAML, and JUnit/Mockito unit and integration tests with coverage and Cucumber automation. 【Book Arc note】The excerpt markers cluster heavily in the early-to-middle chapters; the security, resilience, observability, and testing chapters are described in the table-of-contents-style summary rather than shown in depth. 【Key Takeaways】 - **Auto-configuration is the framework's core trick** (Early): conditional beans like `@ConditionalOnClass` explain why dependencies "just work" — understanding this lets you override defaults deliberately instead of fighting them. - **Starters bundle dependencies and versions** (Early): `spring-boot-starter-parent` and starter packs (web, security, data) remove version bookkeeping; the book shows what each pulls in and how to exclude or change versions before deployment. - **Annotations are the configuration language** (Early): `@Component`/`@Configuration`, `@Autowired` (including collections and maps), `@Lazy`, `@Async`, `@Scheduled`, and `@Profile` are each demonstrated with runnable snippets. - **Data access scales from simple to structured** (Middle): JdbcTemplate for direct SQL, then Spring Data JPA repositories with entity mappings and query methods; H2 is the learning sandbox, MySQL the realistic target. - **Caching is a one-annotation win** (Middle): `@Cacheable` plus `@EnableCaching` turns a slow repeated query into a fast one — the book shows the timing difference concretely. - **REST APIs need validation and error handling** (Middle): `@ControllerAdvice` converts validation failures into controlled responses instead of raw HTTP 500s, a detail many tutorials skip. - **Microservices need discovery and resilience** (Late): Eureka registration by `spring.application.name`, RestTemplate calls, client-side load balancing, and circuit breakers that degrade gracefully rather than cascade failures. - **Production readiness is a checklist** (Ending): security (filters, OAuth 2.0), structured logging and distributed tracing, Swagger docs, and JUnit/Mockito/Cucumber tests with coverage — the book treats these as part of the build, not afterthoughts. 【Reading Tips】 - **Deep-read the early configuration and annotation chapters** — they explain the "why" behind everything later; skimming them makes the microservices chapters feel like magic. - **Skim the installation and IDE screenshots** (Opening) if your environment is already set up; they are step-by-step setup, not concepts. - **Type the code, don't just read it** — the value is in running the H2-to-MySQL switch, the caching timing demo, and the controller-advice error handling yourself. - **Treat the late chapters as a map, not a tutorial** — security, tracing, and testing are summarized at overview level in the excerpts; plan to consult official docs for depth. - **Keep the "Points to Remember" boxes** as your revision sheet; they condense each chapter's practical gotchas. 【Coverage Limits】 The excerpts are front-loaded: configuration, annotations, data access, and REST are well represented, while security, load balancing, circuit breakers, logging/tracing, Swagger, and testing appear mainly as chapter summaries. This guide therefore describes those later topics at the level the source material supports, without inventing implementation detail.