TABLE OF CONTENTS mORB understands a limited IIOP We use this chapter to present mORB a mini-CORBA implementation. Because mORB implements a subset of CORBA, the technical terms used in this chapter are CORBA based. However, the concepts introduced translate to other middleware technologies as well. The goal is to use a compact, easy-to-understand version to describe the elementary components of a middleware platform. Although mORB only comprises a few hundred lines of program code, it is still possible to execute the bank application on it. Moreover, the bank application under mORB is interoperable over IIOP to its CORBA counterpart; that is, the clients and servers of mORB and CORBA can be combined in any combination.
Our aim is to keep the implementation of mORB as compact as possible. Consequently, we have limited its functionality considerably compared to CORBA-compliant middleware. Despite these limitations, we are able to explain the key concepts that are helpful in understanding the Mico architecture. Moreover, mORB is suitable as an experimental platform for other modifications. The complete source code for mORB is available at www.mico.org/textbook/.
From a programming standpoint, mORB is a C++ program library that is linked to an application. Figure 4.1 shows the relationship between mORB, an application that is run on mORB, and the underlying operating system. The internal structure of mORB, which is highlighted in Figure 4.1 by a black border, is based on a...
