EmbeddedServletContainer.start() causes errors if called multiple times

[kuhnroyal]

As stated in the docs this should not create errors, specifically port binding errors with undertow but looking at the code it will most likely fail with other containers as well.

Calling this method on an already started container has no effect.

public interface EmbeddedServletContainer {

	/**
	 * Starts the embedded servlet container. Calling this method on an already started
	 * container has no effect.
	 * @throws EmbeddedServletContainerException if the container cannot be started
	 */
	void start() throws EmbeddedServletContainerException;

       ...
}

I am trying to start the embedded container very early by manually calling start() but the EmbeddedWebApplicationContext will always call start() again and the application fails to start.
Implementations of EmbeddedServletContainer should safe guard from this behavior.

[kuhnroyal]

@philwebb Thanks!