Difference between JAR,WAR and EAR

Hi all,,

Can anybody help me out when Jar,War and Ear files are used.I don't have any knowledge about these things.I don't know how to use in web applications.

Please help me out with clear cut explanation.

In which situation we need to go for which file.Who introduced these types of files and how to deploy them.

Thanks............

1. Java Archives (JAR) A JAR file encapsulates one or more Java classes, a manifest, and a descriptor. JAR files are the lowest level of archive. JAR files are used in J2EE for packaging EJBs and client-side Java Applications.

2. Web Archives (WAR) WAR files are similar to JAR files, except that they are specifically for web applications made from Servlets, JSPs, and supporting classes.

3. Enterprise Archives (EAR) ”An EAR file contains all of the components that make up a particular J2EE application.

Hi Subramani,

Great thanks for your detailed explanation of topic.

I have one more question,it seems to be simple & silly but i have some confusions over that.

What is difference between Web Application & Enterprise Application? what these applications comprises and based on which factors we will decide which is Web or Enterprise Application?.

Thanks.........

You create an Enterprise Application when your application consists of multiple items. For example: 1 Web Application and two EJB Modules.
By doing this you only have to deploy 1 file on an application server (the .ear file)

Hi Nico,

nice and straight description,i got the point what you said.

As per my knowledge is concerned, JAR files are introduced by Java People. Likewise who introduced War and Ear files.

I know that we can create & deploy jar files in 2 ways. 1)Through Command Prompt 2)Through IDE.

Same way how to create & deploy these Ear & War files?

Yes, WAR files can be created using the standard Java jar command