How do I launch a Spring Boot application without the embedded tomcat?

Question

I have a Spring Boot application which was generated using jhipster, and it works fine. However, I also need to create a second application for some back-office batch jobs, and this application uses most of the spring services of the first application. What I did is create a second main class, which starts a spring boot application. The problem is this also starts the embedded web-server and all the services that are only useful for the web app. I only need the services, persistence and other classes that are not specifically tied to the GUI.

Here are my two main classes (simplified)

The normal spring-boot app:

@ComponentScan
@AutoConfigure
class Application {
    public static void main(String[] args) {
        SpringApplication app = new SpringApplication(Application.class)
        app.run(args)
    }
}

The back-office app:

@ComponentScan
@AutoConfigure
class BackOfficeApplication {
    public static void main(String[] args) {
        SpringApplication app = new SpringApplication(BackOfficeApplication.class)
        app.run(args)
    }
}

What works: My back office application has access to everything that I need. Spring services, beans, etc. The problem: The back office app starts the GUI, preventing me to launch it twice at the same time.

Is there a way to deactivate the launching of the embedded tomcat server? Otherwise, is there a way to load the spring application context in another way that wouldn't start the embedded server ?

Some details: * I don't start the app by using mvn spring-boot:run. I launch the class directly with java (or using eclipse

Answer 1

SpringApplication has a property webEnvironment. It defaults to true if Tomcat is on the classpath but you can set it to false (programmatically or with spring.main.webEnvironment).