Hey there, since your Spring Initializr-generated project works on other systems but fails on yours, we can narrow this down to environment-specific issues on your machine. Let’s walk through the most common fixes step by step:

1. Verify Java Version Compatibility #

Spring Boot has strict Java version requirements—for example:

• Spring Boot 3.x requires Java 17 or later
• Spring Boot 2.7.x supports Java 8, 11, and 17

Run these commands in your terminal to check your current versions:

java -version
mvn -v

Compare the output with the <java.version> value in your pom.xml. If they don’t match, install the correct Java version and update your JAVA_HOME environment variable.

2. Check for Port Conflicts #

The default Tomcat port (8080) might be occupied by another application (like a web server, database, or even another Spring Boot app).

• Windows: Run this command to find the process using port 8080:

  netstat -ano | findstr :8080
  

  Then kill the process with taskkill /F /PID <process-id>.

• Linux/macOS: Use this command to locate and terminate the process:

  lsof -i :8080
  kill -9 <process-id>
  

Alternatively, change the Tomcat port in src/main/resources/application.properties:

server.port=8081

3. Fix Corrupted Maven Dependencies #

Your local Maven repository might have corrupted or incomplete dependency files. Try cleaning and re-downloading dependencies:

1. Delete the Spring-related folders in your local Maven repo (usually at ~/.m2/repository/org/springframework on Linux/macOS, or C:\Users\<your-name>\.m2\repository\org\springframework on Windows).
2. Run this command in your project directory:

   mvn clean install
   

4. Validate Your Full pom.xml #

The snippet you shared is incomplete—make sure these critical sections are present and correct:

• The Spring Boot parent dependency (this manages all versioning):

  <parent>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-parent</artifactId>
      <version>your-boot-version</version>
      <relativePath/>
  </parent>
  

• The web starter (which includes embedded Tomcat):

  <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
  </dependency>
  

5. Share the Exact Error Logs #

The most helpful info is missing here—what’s the exact error message in your console? Run mvn spring-boot:run and copy the full error stack trace. Common issues include:

• Address already in use (port conflict)
• UnsupportedClassVersionError (Java version mismatch)
• NoClassDefFoundError (missing dependencies)

Once you share the logs, we can pinpoint the exact problem faster!

内容的提问来源于stack exchange，提问作者Jayanta Rijal