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Ace the coding interview

From Big O to solved interview problems, in the order interviewers expect you to know them.

For you if: You have a coding interview coming up, or you want to stop freezing on algorithm questions.

  1. Big O Notation in Java: Time and Space Complexity for Coding Interviews 22 min read
  2. Java Data Structures: Which One to Use and Why (with a Big-O Cheat Sheet) 11 min read
  3. From O(n²) to O(n): Replace Nested Loops with a HashMap in Java 9 min read
  4. Binary Search Tree in Java: Insert, Search, Delete and Traversal (with GTIN Example) 17 min read
  5. Depth-First Search (DFS) in Java: Graph Traversal Explained, with BFS 21 min read
  6. Merge Two Sorted Lists in Java: Array List and Linked List Solutions 14 min read
  7. Items in Containers: Count Items in Closed Compartments (Code Interview Problem) 7 min read
  8. Shopping Options: Count the Ways to Buy Within a Budget (Code Interview Problem) 16 min read
Cover of The Code Interview
Finish the path with my book The Code Interview

Real Java coding interview questions, each solved step by step, with the thinking you are expected to say out loud.

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Build REST APIs with Spring Boot

Design, build, document, secure and call a REST API, the way it is done in real projects.

For you if: You build backends in Java and want APIs that other teams can use without asking you how.

  1. REST API Tutorial: Resources, HTTP Methods, Status Codes and a Spring Boot Example 19 min read
  2. Build a RESTful Web Service with Spring Boot, Gradle, and OpenAPI 7 min read
  3. Design-First APIs with OpenAPI 3: A Step-by-Step Tutorial 8 min read
  4. Document a Spring Boot REST API with OpenAPI 3 and Swagger UI (springdoc) 28 min read
  5. Generate a Spring Boot Server from an OpenAPI Spec with Swagger Codegen 7 min read
  6. Secure a Spring Boot REST API with OAuth2 and OpenAPI (Swagger UI) 12 min read
  7. Rate Limiting in Spring Boot with Bucket4j: Token Bucket Algorithm per Client 13 min read
  8. How a REST Client Should Handle 503 Service Unavailable: Retries with Backoff in Spring 14 min read
  9. Replace OAuth2RestTemplate with RestClient: A Modern Spring Boot API Client 11 min read
Cover of Designing APIs with Swagger and OpenAPI
Go further Designing APIs with Swagger and OpenAPI

The book I recommend for going deeper into design-first APIs and the OpenAPI specification.

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Design better software

Object-oriented basics, SOLID and clean code, so your code stays easy to change.

For you if: Your code works, but every new feature breaks something else.

  1. OOP Concepts in Java: The 4 Pillars and Composition, with Examples 13 min read
  2. Software Design Principles Explained with Java Examples: SOLID, DRY, KISS, YAGNI and More 14 min read
  3. SOLID Principles in Java: The Definitive Guide with Examples 20 min read
  4. Open-Closed Principle in Java with a Spring Boot Example (SOLID Part II) 14 min read
  5. Clean Code Best Practices: 10 Rules with Java Examples 25 min read
  6. UML Diagrams for Java Developers: From Requirements to Code 13 min read
  7. Ubiquitous Language in Domain-Driven Design: How to Build One, with Java Examples 8 min read
Cover of Software Design Principles
Finish the path with my book Software Design Principles

All the principles in one place, with Java examples you can apply on Monday morning.

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