Basic Web Application Structure

A lot of components go into making a Java EE application.

  • Application Code and Third Party Libraries it depends on
  • Deployment Descriptor, which includes instructions for deploying and starting the application
  • ClassLoders which is responsible for isolating your application form other web applications on the same server
  • Finally the WAR and EAR files

Servlets, Filters, Listeners, and JSPs

  • Servlets are a key component of any Java EE applications. Servlets are Java classes responsible for accepting and responding to the HTTP request.

  • Nearly every request to your application goes through a Servlet of some type, except those requests that are erroneous or intercepted by some other component. Filter is one such component that can intercept requests to your Servlets.

  • Java EE web applications support various types of listeners, which can notify your code of multiple events, such as application startup, application shutdown, HTTP session creation, and session destruction.

  • And finally, we have jsp(JavaServer Pages), which provides you with the means to easily create dynamic, HTML based graphical user interfaces for web applications.