A clear understanding of C++ objects is fundamental to using Concert Technology with CPLEX to build and solve optimization models. These objects can be divided into two categories:

Modeling objects are used to define the optimization problem. Generally an application creates multiple modeling objects to specify one optimization problem. Those objects are grouped into an IloModel object representing the complete optimization problem.
IloCplex objects are used to solve the problems that have been created with the modeling objects. An IloCplex object reads a model and extracts its data to the appropriate representation for the CPLEX optimizer. Then the IloCplex object is ready to solve the model it extracted and be queried for solution information.

Thus, the modeling and optimization parts of a user-written application program are represented by a group of interacting C++ objects created and controlled within the application. Figure 3.1 shows a picture of an application using CPLEX with Concert Technology to solve optimization problems.

Figure 3.1 A View of CPLEX with Concert Technology

The CPLEX database includes the computing environment, its communication channels, and your problem objects.

In this chapter we give a brief tutorial illustrating the modeling and solution classes provided by Concert Technology and CPLEX. More extensive coverage of the modeling classes can be found in the chapter about IloCplex in the ILOG Concert Technology User's Manual and in the ILOG Concert Technology Reference Manual. More information about the algorithm class IloCplex and its nested classes can be found in the ILOG CPLEX User's Manual and ILOG CPLEX Reference Manual.