Crosscutting Use Cases

Moreira et al. [34] proposed an approach to identify crosscutting concerns among the quality attributes that affect functional use cases. Araújo and Moreira [35] augmented the identification of crosscutting concerns by using use cases specification to represent functional and nonfunctional requirements. Based on the work of Araújo and Moreira [35], Eler [36, Chapter 4.4.10] proposed guidelines to identify crosscutting use cases based on the use case diagram, which does not necessarily mean that these crosscutting use cases will be implemented by aspects. The criteria to identify crosscutting use cases are the number of relationships with other use cases. The criteria are listed below.

• Use cases included by two or more use cases;
• Use cases that extend two or more use cases;
• Use cases that constrain two or more use cases. The constrain relationship between use cases was proposed proposed by Araújo and Moreira [35].

Thus, based on the use case diagram (Figure 7), two crosscutting use cases have been identified. Table 4 presents crosscutting use cases and the criteria applied to identify them.

Table 4: Crosscutting use cases

Use cases	Criteria
Encrypt data	It extends two or more use cases
Persist data	It is included by two or more use cases
Handle exception	It extends two or more use cases
Provide remote access	It extends two or more use cases