Difference of META-INF and WEB-INF

[geetareddy]

What META-INF and WEB-INF contains.

[sumittyagi]

What META-INF and WEB-INF contains.

These folders contains private information about the application.
META-INF
Now Meta-inf could contain information about the ejb components or any standalone application (desktop application, such as in swing). Its main content is Manifest.mf file. This file contains Meta-data, i.e data about data. for example in stand alone application it contains info about which class contains the main function, so that system could load that class.(a lot of other meta-data could be included in it.

WEB-INF.
Now web-inf contains information, and data about the web application. It contains servlet classes, and other library/utility classes; it could also contain properties files. It could contain any other information which you want to keep private.

That's All.

[sateesht]

Each web application should be contained in a war (web archive) file. War files are nothing but a jar file containing atleast one descriptor called web.xml. The file structure of war file is:

 
  /--
 
    |
 
    | WEB-INF
 
    |   |
 
    |   |-- WEB.XML (Deployment descriptor)
 
    |   |-- classes (Folder containing servlets and JSPs
 
    |
 
    | META-INF
 
    |   |
 
    |   |-- MANIFEST.MF
 
    |
 
    | all utility files and resources like error pages etc.
 

Each enterprise bean is stored in a jar file. The jar file contains all standard files like manifest and atleast one additional file called ejb-jar.xml. The structure of a jar file is:

  /--
 
    |
 
    | META-INF
 
    |   |
 
    |   |-- MANIFEST.MF
 
    |   |-- ejb-jar.xml
 
    |
 
    | all classes as in a normal jar file.
 

Both jar and war files are placed inside a ear (enterprise archive) file. The structure of an ear file is

  /--
 
    |
 
    | META-INF
 
    |   |
 
    |   |-- MANIFEST.MF
 
    |   |-- application.xml
 
    |
 
    | jar and war files.
 

TODO may be we should add the structure of all the deployment descriptors here as well.


Cheers,
Sateesh.