From the end customer's point of view, .jar file is a package, they don't need to know how many .class files in the .class file, the functions and functions in each file, can also get the results of their hopes. There are WAR and EAR for J2ee except JAR. See the table below:
Jar War Ear ENTERPRIVE FILE Web Archive File Enterprise Archive File Contains Content Class, Properties file, is the smallest unit of file packages; servlet, JSP page, JSP tag, JAR library file, HTML / XML document, and other public resource files, Such as pictures, audio files, etc. In addition to including JAR, WAR, including EJB component deployment file Application-Client.xml Web.xml Application.xml level small medium
