What is the difference between a .war and .ear file?
To make the project transport, deployment made easy. need to compressed into one file. JAR (java archive) group of .class files
WAR (web archive) - each war represents one web application - use only web related technologies like servlet, jsps can be used. - can run on Tomcat server - web app developed by web related technologies only jsp servlet html js - info representation only no transactions.
EAR (enterprise archive) - each ear represents one enterprise application - we can use anything from j2ee like ejb, jms can happily be used. - can run on Glassfish like server not on Tomcat server. - enterprise app devloped by any technology anything from j2ee like all web app plus ejbs jms etc. - does transactions with info representation. eg. Bank app, Telecom app