Architecture for spring enterprise web application
I need understand what architecture use in new project. We want to use GWT & spring mvc as the base. 
Also we have about 100 entities in domain model, which need to persist in DB. So we are likely to use Hibernate as ORM solution. 

1. I can't understand what application server we should use? Can we get tomcat or there is best solution for enterprise application in our case? Suggest me please.

2. How tomcat serves http requests, which need database operation through hibernate? 

3. When spring applicationContext.xml is read? During Each http request or not?

4. Using Spring+Hibernate+JPA is fast way in case of middle load application?

Architecture for spring enterprise web application
===

I need understand what architecture use in new project. We want to use GWT & spring mvc as the base. 
Also we have about 100 entities in domain model, which need to persist in DB. So we are likely to use Hibernate as ORM solution. 

1. I can't understand what application server we should use? Can we get tomcat or there is best solution for enterprise application in our case? Suggest me please.

2. How tomcat serves http requests, which need database operation through hibernate? 

3. When spring applicationContext.xml is read? During Each http request or not?

4. Using Spring+Hibernate+JPA is fast way in case of middle load application?
