control modifier Attribute

The "modifier" attribute of the <control> element specifies the override requirements for the control block.

If ABSTRACT, the block may not include a body. The body must be specified by non-abstract derived components. Control blocks may only be declared abstract if the component is also declared abstract. Abstract blocks may not be private. Non-abstract blocks must declare a body.

If FINAL, the control block may not be overridden by derived components.

If unspecified, then derived components can choose whether or not to override the block.