How can I know that which version of entirex.jar file are running in my java project

We have some different java project there we are using different versions and different sizes entirex.jar file.
How can I know that which entirex.jar file is coming from which version of entirex?
There has any way to get that version information from developer side as well as DBA side?

did you check the file
META-INF\MANIFEST.MF
in the jar file?
it should include version info.

No, In there has no jar file. There has only below info:

Manifest-Version: 1.0
Class-Path:

Problem is, project building time entirex.jar file may not be same with current version, because sometimes entirex version upgraded, and developer put the latest version of entirex.jar file in the project lib folder. Since old version of entirex.jar and new version of entirex.jar all are same name, but we need to know actuaaly which one is for which version.