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Packaging Applications

  • The enterprise application is delivered to the client as a .ear file having a no of .jar files, settings, other libraries , deployment descriptors and other web resources.
  • A deployment descriptor is an XML document with an .xml extension that describes the deployment settings of an application, a module, or a component.
  • At runtime the J2EE container reads the deployment descriptors and acts upon the application, module or component accordingly.
  • Two types of Deployment descriptor
    • J2EE Deployment Descriptors:-Defined by the J2EE Specification. It can be used to configure settings for any J2EE compliant implementation.
    • Runtime Deployment Descriptors: - It is used to configure J2EE implementation specific parameters.
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