As per the new proposal made in JCA 1.6 and Java EE 6 platform spec, Java EE
implementations are allowed to limit visibility of a standalone RAR to only
those applications that depend on that RAR. See section 126.96.36.199 and 19.3 of JCA
1.6 EDR. The feature implementation involves the following:
1. an API from deployment module that can be used to find standalone RARs used
by an application.
2. Create ConnectorClassLoader per application with appropriate list of connectors.
3. Change RAR undeployment code to throw exception when a RAR is undeployed
while it is still being referred by some application. Decide whether --force is
needed for undeploy command. Same is true for redeployment.