[FIXED] AWS Beanstalk + Kotlin + Spring boot: NoSuchMethodException main()

Issue

I've a Spring Boot app written in Kotlin that I have deployed to AWS Beanstalk that is throwing the following exception:

Exception in thread "main" java.lang.NoSuchMethodException: com.prototype.demo.DemoApplication.main([Ljava.lang.String;)
at java.base/java.lang.Class.getDeclaredMethod(Class.java:2675)
at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:47)

Locally, when I run the app from IntelliJ I've no issues. I have the spring-boot-maven-plugin and the kotlin-maven-plugin in my project.

Any ideas about what could be causing the issue? I previously built a similar app in Java but didn't run into this issue.

Thank you for your expertise and time.

---

Update: something interesting to notice is that I had to set in the properties of my POM the following line in order to make the project executable by IntelliJ during development (i had forgotten about it): <start-class>com.prototype.demo.DemoApplication</start-class>

Now I've removed it and I get a different error when running the jar file. I will spend some time on it and see if that's related or not and update the question accordingly. Thank you!

Solution

The issue was raised by the following property declared in my POM file: <start-class>com.prototype.demo.DemoApplication</start-class>. Once I removed it and added the open keyword to the Configuration annotated classes and to the DemoApplication(the class containing the main) it finally worked.

Answered By - Marco
Answer Checked By - Mildred Charles (JavaFixing Admin)