In much the same way that individual OSGi bundles can be versioned, Virgo allows applications to be versioned. How exactly you do this depends on how you have packaged the application:
Application-Versionheader in the
MANIFEST.MFfile of the PAR file.
versionattribute of the
<plan>root element of the plan’s XML file.
Bundle-Versionheader of the
MANIFEST.MFfile of the bundle.
Virgo uses an application’s version to prevent clashes when multiple versions of the same application are deployed at the same time. For example, the application trace support described in Section 4.9, “Application Trace”, includes the application’s name and version in the file path. This ensures that each version of the same application has its own trace or logging file.