1. What is Spring Cloud Gateway? Spring Cloud Gateway is a library that provides API gateway functionality. It allows you to: Route requests to different microservices Apply filters (like authentication, logging, rate limiting) Handle cross-cutting concerns in a microservice architecture It’s the modern alternative to Netflix Zuul. 2. Project Setup You can use Spring…
1. Spring Boot Overview Spring Boot is a framework that simplifies creating production-ready Spring applications. Key points: Provides embedded servers (Tomcat, Jetty), so you don’t need to deploy WAR files. Auto-configuration reduces boilerplate code. Supports microservices architecture. 2. Spring Cloud Config Overview Spring Cloud Config provides centralized configuration management for distributed systems. It allows…
1. Spring Boot Setup Suppose we have a simple app that manages users. User model: package com.example.demo.model; public class User { private Long id; private String name; // Constructors public User() {} public User(Long id, String name) { this.id = id; this.name = name; } // Getters & Setters public Long getId() { return…
1. Add Dependencies In pom.xml (for Maven) or build.gradle (for Gradle), add the following: Maven: <dependencies> <!-- Spring Boot starter for JPA --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <!-- PostgreSQL driver --> <dependency> <groupId>org.postgresql</groupId> <artifactId>postgresql</artifactId> <scope>runtime</scope> </dependency> <!-- Testcontainers dependencies --> <dependency> <groupId>org.testcontainers</groupId> <artifactId>testcontainers</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.testcontainers</groupId> <artifactId>postgresql</artifactId> <scope>test</scope> </dependency> <!-- Spring Boot Test…
1. What is Spring Boot? Spring Boot is a framework that simplifies creating standalone, production-ready Spring applications. It provides: Auto-configuration Embedded servers (Tomcat/Jetty) Opinionated defaults Easy dependency management 2. What is JUnit? JUnit is a testing framework for Java, mainly used for unit testing. With Spring Boot, we often use JUnit 5 along with…
Apache Camel is an open-source integration framework that helps developers connect different systems, applications, and services in a flexible and standardized way. It is primarily used for enterprise integration patterns (EIPs), which are common design patterns for integrating systems. from("file:input"). filter(body().contains("Camel")) .to("file:output");from("file:input"). filter(body().contains("Camel")) .to("file:output"); 1. Add Dependencies In pom.xml (Maven project), include: <dependencies> <!--…
1. What is Spring Batch? Spring Batch is a lightweight framework for batch processing, which is processing large volumes of data in chunks. Key features: Chunk-based processing Transaction management Retry and skip logic Job scheduling Integration with databases, files, queues, etc. 2. Basic Concepts TermDescriptionJobA batch process; contains one or more steps.StepA phase of…
Spring Boot Shell allows you to create interactive command-line applications using Spring Boot. It’s ideal for building CLI tools. Here’s a complete example: 1️⃣ Add Dependencies In your pom.xml (for Maven): <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter</artifactId> </dependency> <dependency> <groupId>org.springframework.shell</groupId> <artifactId>spring-shell-starter</artifactId> <version>3.1.2</version> <!-- Use latest --> </dependency> </dependencies> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter</artifactId> </dependency> <dependency> <groupId>org.springframework.shell</groupId> <artifactId>spring-shell-starter</artifactId>…
🔹 What is AOP? AOP lets you separate cross-cutting concerns (like logging, security, transactions, caching) from business logic.In Spring Boot, AOP is usually implemented using Spring AOP with annotations like @Aspect. 🔹 Key Concepts Aspect → @Aspect Advice → @Before, @After, @AfterReturning, @AfterThrowing, @Around Pointcut → @Pointcut Join Point → (no annotation; accessible via…
A Resource Server is an application that serves protected resources and validates access tokens issued by an Authorization Server (like Keycloak, Okta, Auth0, or a custom Authorization Server). 🔑 Core Concepts Authorization Server → Issues tokens (JWT, opaque). Example: Keycloak, Auth0. Resource Server → Your Spring Boot REST API that checks tokens before serving…