Static objects in Weblogic

Question

Is it possible to install a static object at the ManagedServer level that is visible to multiple applications? I'm aware of shared libraries, but it isn't clear to me whether that is simply a deployment convenience where each app gets its own copy in memory. An example might be a global cache.

Answer 1

With shared libraries you can share static resources among applications. For instance if you want to share an image among multiple apps you could add the following to your weblogic.xml:

<wls:library-ref>
    <wls:library-name>my_shared_library</wls:library-name>

And if that shared library contained an image, you could reference it directly like:

<img src="my_shared_library.gif"/>

See more here:

https://blogs.oracle.com/jamesbayer/entry/weblogic_server_shared_librari

You can also share a class in a similar manner if you are looking to shared a singleton across multiple apps. Simply create your shared class, jar it up, and drop it into the DOMAIN_HOME/lib directory. This will force weblogic to use the same class loader for all apps, meaning your shared class is only instantiated once. See more here:

https://blogs.oracle.com/jamesbayer/entry/sharing_a_class_with_a