Java Spring multiple ApplicationContext

Question

The definition of the spring ApplicationContext is very ambiguous, I almost finish a whole book of tutorial but still cannot understand what is the Applic

Answer 1

ApplicationContext is an implementation of a Spring container. In simple words Spring container manages the entire Spring application via an ApplicationContext. Spring container via ApplicationContext manages the life cycle of a Spring bean i;e from initiation to destruction.

A spring container is nested inside a J2EE container.

I keep seeing the book mentioned "container", what is the container refer to? One container does it mean one java process? or one container refer to one ApplicationContext object?

A container manages the life cycle of an object. Tomcat is a an example of a container. Just like Spring container manages the app via ApplicationContext a J2EE container Tomcat manages the app via web.xml

A container provides communications support. Security in a web application. JSP support, Internationalization, event-propagation & many other features. It supports multithreading, spawns a new thread for every request for a resource. You don't have to explicitly write the code for that. Just like a spring container, a J2ee container manages a servlet life cycle.

If i instantiate two ApplicationContext in one java application (one Main body), are these two interface to one central container?

If you want to instantiate multiple ApplicationContexts in your application. It will be in a parent child hierarchy. There will be one root ApplicationContext & then there will be child ApplicationContext respective to every DispatcherServlet. Beans global to the application will be defined in the root ApplicationContext. All the ApplicationContexts will be managed by only one spring container.