Heavy Loaders 

Heavy loaders load application classes with highest priority.

How They Work

Heavy loaders work in the following manner:

●      Created with the resources located in the lib folder in the root if the EAR, only when the application version is Java EE 5.

●      First in the parent list. This guarantees the following delegation order when loading a resource:

¡        Heavy loader (and its parent, respectively).

¡        Default references, specified by the containers during deploy. Usually contain the standard Java EE APIs.

¡        Application specific references (specified in the application-j2ee-engine.xml).

¡        All other application resources contained in the EAR.

Activating Heavy Loaders

To activate the heavy loaders:

...

       1.      Switch on the heavy loaders behavior, since it is switched off by default :

                            a.      Start the Config tool.

                            b.      Change the Define_Heavy_Resources property of the library_container to true.

                            c.      Save the change.

                            d.      Restart the whole instance for the change to take effect.

       2.      Check that the heavy loader is created and contains all custom JARs (for example, provided that you have packed the custom JARs as a bundled library for heavy class loading in the application named com.vendorX/Hibernate).

                            a.      Using telnet, enter:

>ll | grep com.vendorX/Hibernat|e

                            b.      You should get as output two class loaders:

[com.vendorX/Hibernate]

[com.vendorX/Hibernate-library-loader]

The second one is the heavy class loader.