Application management, including deployment, has remained mostly unchanged since WAS 5.
WAS 7, however, introduced a new concept -- "Business Level Applications" (BLA). It would be more accurate to use the term "composite application" because this is what BLAs are -- it's a composition of Java EE applications (WARs or EARs) or other "assets".
Unfortunately, the term "composite application" is already used in a different context by IBM.
The word "asset" is another confusing and terribly overused term. In WAS7 it's a "catch all" word for any kind of artifact, including jar, zip, and, with the introduction of OSGi support, an OSGi bundle (you need to have a beta OSGI feature pack installed to be able to use OSGi).
BLAs are created by combining applications and assets together either using admin console or scripting. BLA configuration is saved under $profile_root/config/cells/$cell_name/blas. Assets are saved under $profile_root/config/cells/$cell_name/assets.
I can see two use cases for BLAs:
AdminTask.startBLAprovide an easy way to restart several "regular" applications.
AdminTask.importAssetcommand. You can then reference the jar file using "SharedLibRelationship" option of AdminApp install/update commands. This will automatically create a classloader for this library (note--this might require server restart, at least for me it did). Being able to use regular administration APIs for managing shared libraries is certainly a welcome feature.
Unfortunately, BLAs also have limitations:
To summarize, the BLA idea has some promise but its current implementation is too limited to be truly useful. I'm sure IBM will be evolving BLA in future WAS releases.
You can find more information about BLA in this article .
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