为什么grails无法在同一端口上运行两个应用程序？

Question

With Tomcat or Glassfish, there is no problem with deploying multiple apps on port 8080. But if you try to do a grails run-app on multiple apps (without specifying different ports) at the same time, you will receive a JVM Bind Exception.

Why is grails run-app different from deploying a .WAR to a container?

Answer 1

deploying a .WAR to a container

The container itself is bound to a port. The container (Tomcat, Glassfish, whatever) has the ability to host multiple applications

grails run-app

Spins up its own container that is bound to a port. This container may have the ability to host multiple apps, but that isn't what you're doing when you type "run-app"

Answer 2

I'm no grails expert, but Tomcat and Glassfish are one process/application bound to one port. Then they host different applications (web/enterprise) running in the same VM, and route requests using the context root for example.

I suspect grails run-app starts a new application as a new process/in a new JVM instance and tries to bind it to the port. If there's already a binding, that won't work.