Kinh nghiệm - Thủ thuật

For object-oriented systems the concept of a structure chart and hierarchical calling relationships are not applicable. Therefore, integration

needs to proceed in a manner different from described previously. A good approach to integration of an object-oriented system is to make use of

the concept of object clusters. Clusters are somewhat analogous to small subsystems in procedural-oriented systems.

A cluster consists of classes that are related, for example, they may work together (cooperate) to support a required functionality for the complete system.

For purposes of illustration we assume that they cooperate to perform functions whose result (Out message) is exported to the outside world. As another illustration

of the cluster concept we can use the notion of an object-oriented system that manages a state vehicle licensing bureau. A high-level cluster of objects may be concerned with functions related to vehicle owners, while another cluster is concerned with functions relating to the vehicles themselves. Coad and Yourdon in their text on object-oriented analysis give examples of partitioning the objects in a system into what they call subject layers that are similar in concept to clusters. The partitioning is based on using problem area subdomains [20]. Subject layers can be identified during analysis and design and help to formulate plans for integration

of the component classes.