Application Servers

1
Application Servers

• What is it?
• General
• A set of software frameworks, components,
  utilities, functionality that enables you to
  develop and deliver n-tiered web applications
• Specific
• A software package that implements all of the
  J2EE APIs and frameworks that allow you to
  develop and deliver J2EE applications

2
Application Servers

• A J2EE Application Server provides (at a
  minimum)
• Servlet engine/container
• EJB engine/container
• Web Server (or ability to integrate with a web
  server)
• Concrete implementations of all the J2EE APIs
• Java Mail
• Messaging
• RMI
• Others
• A vendor-bought App Server will also have
  additional functionality in addition to the J2EE
  functionality

3
Application Servers

• Products
• Full J2EE App Servers
• BEA Web Logic
• IBM Websphere
• Oracle App Server
• JBoss (FREE / open source)
• Many others
• Others
• Tomcat (servlet only - FREE)
• http//www.theserverside.com/reviews/matrix.jsp

4
Application Servers

• Do I need one?
• If you want to deliver any kind of web
  application with java, you at least need a
  Servlet engine
• Start with Tomcat, its free
• Many organizations dont go further than this
• If high volume / high availability are issues,
  consider