Testing the individual operations associated with objects - These are functions or procedures and the black-box and white-box approaches may be used.
Testing individual object classes - the principles of black- box testing is and unchanged but the notion of equivalence class must be extended to cover related operation sequences.
Testing clusters of objects - Strict top-down or bottom-up integration may bein appropriate to create groups of related objects. Other approaches such as scenario-based testing should be used.
Testing the object-oriented system - V & V against the system requirements specification is carried out in exactly the same way as for any other type of system.
The testing in isolation of all operations associated with the object.
The setting and interrogation of all attributes associated with the object.
The exercise of the object in all possible status. This means that all even that cause a state change in the object should be simulated.
In object-oriented systems, there is no obvious ‘top’ that provides for the integration nor is there a clear hierarchy of objects that can be created. Clusters, therefore, have to be created using knowledge of there operation and the features of the system that are implemented by these clusters. There are three possible approaches an integration testing that may be used.
Use-case or scenario-based testing - Testing can be based on the scenario descriptions and object clusters created to support the use-cases that relate to the mode of use.
Thread testing - Thread testing is based on testing the system’s response to a particular input or set of input events.
Object interaction testing - An intermediate level of integration testing can be based on identifying ‘ method- message’ paths. These are traced through a sequence of object interactions which stop when an object operation does not call on the services of any other object.