SAR (Service Archive)

SAR file is created with the .sar extenstion same like how other archive files (JAR, WAR, EAR) created. But the purpose of the SAR file is differenet from the other archive files. It is used for deploying a service component in the application server without dependent on other componenets. You can create a seperate componenet as a SAR file and deploy it in the server. When application server starts, the component will be deployed and started running independently. Most of the times these SAR files are used for writing thread related components which has to be running independently.

JBoss's service archive architecture is based on the Java Extension Management (JMX). During the server bootup process, the service archive deployer (SARDeployer) instantiates the JBoss service classes and exposes them as manageable beans through JMX. You can view all of registered JBoss service components in the JBoss JMX Console web application.