Spring Boot DevTools
DevTools for development: live reload, automatic restart, dev configurations, remote debugging
1What is Spring Boot DevTools?
What is Spring Boot DevTools?
Answer
Spring Boot DevTools is a development module that enhances developer experience with features like automatic restart (auto-restart on code changes), LiveReload (automatic browser refresh), and remote debugging. DevTools is automatically disabled in production (detected via JAR/WAR packaging) to avoid performance impact. This optional dependency significantly accelerates the development cycle by reducing manual restarts.
2Which DevTools feature allows automatic browser refresh?
Which DevTools feature allows automatic browser refresh?
Answer
LiveReload is an embedded server that listens on port 35729 and triggers automatic browser refresh whenever a resource (HTML, CSS, JS, images) is modified in the classpath. Unlike automatic restart which restarts the Spring context, LiveReload focuses on front-end assets for immediate visual feedback. A LiveReload browser extension must be installed to establish the WebSocket connection with the DevTools server.
3How to add Spring Boot DevTools to a Maven project?
How to add Spring Boot DevTools to a Maven project?
Answer
DevTools is added as a Maven dependency with optional scope and true in the configuration. The optional scope ensures DevTools won't be transitive to projects depending on yours, while true allows excluding DevTools during production packaging (spring-boot-maven-plugin with excludeDevtools). This double protection ensures DevTools stays strictly in the development environment. The optional scope is the best practice for development-only dependencies.
What is the behavior of DevTools in production?
What is the main advantage of DevTools automatic restart?
+12 interview questions
Other Spring Boot interview topics
Spring Core - IoC & DI
Spring Boot Auto-Configuration
Spring Boot Starters
Application Properties & YAML
Logging with SLF4J & Logback
Spring MVC Basics
Spring REST Controllers
Request & Response Handling
Exception Handling
Bean Validation
Spring Data JPA Basics
JPA Entities & Relationships
JPA Queries
Spring Data Repositories
Spring Security Basics
Spring Boot Actuator
Unit Testing with JUnit & Mockito
Spring Boot Testing
Profiles & Environment
RestTemplate & WebClient
Async & Scheduling
Caching with Spring
Spring WebFlux (Reactive)
Spring Transactions
Advanced Authentication & Authorization
JWT & Stateless Security
OAuth2 & Authorization Server
Spring Boot & Docker
Microservices with Spring
Spring Cloud Config
Performance Optimization
GraalVM Native Images
Master Spring Boot for your next interview
Access all questions, flashcards, technical tests, code review exercises and interview simulators.
Start for free