HelloWorld not working under Spring Boot 3.0.2-CodePudding

This little program

@SpringBootApplication
@RestController
public class HelloworldApplication {

  public static void main(String[] args) {
    SpringApplication.run(HelloworldApplication.class, args);
  }

  @GetMapping(path = "")
  public ResponseEntity<String> sayHello() {
    return new ResponseEntity<>("Hello world!", HttpStatus.OK);
  }

}

gives the expected output on GET localhost:8080 with Spring Boot 2.7.9-SNAPSHOT.

On Spring Boot 3.0.3-SNAPSHOT it only gives a 404 error though. Can anybody tell me how to fix it?

build.gradle:

plugins {
    id 'java'
    id 'org.springframework.boot' version '3.0.3-SNAPSHOT'
    id 'io.spring.dependency-management' version '1.1.0'
}

group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '19'

repositories {
    mavenCentral()
    maven { url 'https://repo.spring.io/milestone' }
    maven { url 'https://repo.spring.io/snapshot' }
}

dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-web'
}

I also tried Spring Boot 3.0.0 and 3.0.2. When I enter "localhost:8080" in the Browser address line, I expect to see "Hello world". Instead, I get a 404 white-label page

CodePudding user response：

The path segment must not be empty.

This will fix your problem:

@GetMapping(path = "/")