A new project using Spring Initializr does not run in browser

Question

Building a new project downloaded using https://start.spring.io/ does not run on browser. I have seen some solutions on stackoverflow which require to make some changes or add, but default/out-of-the-box application does not run.

I asked this in Github https://github.com/spring-projects/spring-boot/issues/20603 but was told that i need to add request mappings or something else. There's no default mapping for the root. That's indeed the default error page showing you a 404.

Is there a documentation to "add request mappings or something else" ? It will help if the application run showing some text instead of an error message. This maybe a simple obvious thing for Spring developers but for learners, takes a lot of effort.

http://localhost:8080/

STEPS TO REPRODUCE:

Download new project at https://start.spring.io/

mvn clean package

mvn spring-boot:run

Answer 1

That is the expected behavior right after creating a fresh Spring Boot project. The initializer does not register any endpoint for you, it just gives you the project skeleton you can start working with.

If you want to see something on localhost:8080/ consider adding the following Java class to your project:

@RestController
public class HelloWorldController {

  @GetMapping
  public String helloWorld() {
    return "Hello World!";
  }

}

If you are new to Spring/Spring Boot, I can recommend the following resources:

• Official Spring Web documentation
• Spring Boot Guides
• Developing a CRUD API with Spring Boot YouTube course