Web Server provides a way of grouping together a collection
of OSGi bundles which comprise a single application.
These bundles are placed in a JAR file with extension “.par
”. This is called a PAR file.
All the bundles in a PAR file are resolved together and so mutual dependencies are permitted.
At runtime a PAR file provides a scope in the sense that bundles inside the PAR file may depend on packages and services outside the PAR file, but bundles outside the PAR file may not depend on packages and services provided by the PAR file.
Virgo also provides the plan artifact as another way of grouping bundles and other artifacts into an application. A plan is a file (in XML format) listing a collection of artifacts. This Guide makes no further reference to plans. See Section A.2, “Documentation” for a link to more Virgo documentation.
PAR files (or individual bundles) are deployed into Web Server by dropping them into a “pickup” directory or using the Administration Console web application provided with Web Server. During deployment, the bundles in the PAR file are installed into OSGi, resolved together, and then started together.