Summary

This chapter described the execution system and its major functions, providing example programs that demonstrate how developers can interact with the execution system. In summary, the execution system provides facilities such as the following:

• Class loading

• Just-in-time compilation and verification

• Memory management and garbage collection

• Security

The execution system may be the source of the biggest difference between the CLR and other component models such as COM and CORBA. COM offers little support for ensuring the type safety of components , accomplishes life-cycle management through developer-controlled reference counting, and supports security as only an afterthought. CORBA provides little in the way of a standardized execution system; under this model, programs execute in the environment offered by the language in which they are written. While this simplicity is helpful for developing distributed systems, it hinders the construction of component-based systems. Facilities such as CORBA's object- by-value will prove difficult to implement for languages that do not supply a common execution environment.