Spring Boot Hello World War File Download Apr 2026

@GetMapping("/") public String hello() return "Hello World from Spring Boot WAR!";

Generate your WAR-ready project at start.spring.io (remember to select WAR packaging), add the five lines of controller code above, and run mvnw package . Your Hello World WAR will be waiting in the target/ folder in less time than it took to read this article.

Inside the extracted project, create a file: src/main/java/com/example/demo/HelloController.java spring boot hello world war file download

For decades, the "Hello World" application has served as the universal rite of passage for developers learning a new framework. In the Spring Boot ecosystem, most tutorials focus on the default—a self-contained JAR file with an embedded server. But what about those who need a classic WAR file for traditional application servers like Tomcat, WebLogic, or JBoss?

From the project root directory, run:

demo-0.0.1-SNAPSHOT.war ├── META-INF/ ├── WEB-INF/ │ ├── classes/ ← Your compiled HelloController.class │ ├── lib/ ← All dependency JARs (excluding Tomcat) │ └── web.xml ← Auto-generated descriptor └── (no embedded Tomcat JARs) Notice what’s : spring-boot-starter-tomcat is marked as provided scope in Maven, meaning the JARs for Tomcat are excluded from the final WAR. Your external server provides those. Common Pitfalls & Fixes | Problem | Likely Cause | Solution | |---------|--------------|----------| | 404 on root URL | No servlet mapping | Ensure SpringBootServletInitializer is extended | | WAR deploys but no Spring features | Missing @SpringBootApplication | Add the main application class | | Port conflicts | External server already bound to port 8080 | Change server’s HTTP port, not your code | The Bottom Line The Spring Boot Hello World WAR file is your bridge between modern Spring development and traditional Java EE deployment infrastructure. While executable JARs dominate newer architectures, the WAR format remains essential for enterprises, shared hosting, and legacy environments.

@RestController public class HelloController In the Spring Boot ecosystem, most tutorials focus

./mvnw clean package (or mvnw.cmd clean package on Windows)

This feature explores the : what it is, why you might need it, and—most importantly—how to download, build, and deploy your own. What Exactly Is a Spring Boot WAR File? A WAR (Web Application Archive) file is the standard packaging format for Java web applications intended to be deployed on an external servlet container. When you create a Spring Boot application as a WAR, you’re telling Spring Boot: “Don’t bundle your own Tomcat. I’ll handle deployment myself.” Your external server provides those

Whether you download a sample, generate one from start.spring.io, or build it manually with a single controller, having a reliable WAR file in your toolkit ensures you’re ready for any deployment scenario—even if that scenario still runs on Tomcat 9 in a data center built a decade ago.