SOMClassMgr class object and SOMClassMgrObject

The third primitive SOM class is SOMClassMgr. A single instance of the SOMClassMgr class is created automatically during SOM initialization. This instance is referred to as the SOMClassMgrObject, because it is pointed to by the global variable SOMClassMgrObject. The object SOMClassMgrObject has the responsibility to

• Maintain a registry (a run-time directory) of all SOM classes that exist within the current process, and to

• Assist in the dynamic loading and unloading of class libraries.

For C/C++ application programs using the SOM C/C++ language bindings, the SOMClassMgrObject automatically loads the appropriate library file and constructs a run-time object for the class the first time an instance of a class is created. For programmers using other languages, SOMClassMgr provides a method, somFindClass, for directing the SOMClassMgrObject to load the library file for a class and create its class object.

Again, the primitive classes supplied with SOM are SOMObject, SOMClass, and SOMClassMgr. During SOM initialization, the latter class generates an instance called SOMClassMgrObject. The SOMObject class is the parent class of SOMClass and SOMClassMgr. The SOMClass class is the metaclass of itself, of SOMObject, and of SOMClassMgr, which are all class objects at run time. SOMClassMgr is the class of SOMClassMgrObject.