Chapter 12, Problem 12RE

Explanation of Solution

“classes”, “responsibilities”, “collaborators” CRC card:

• A CRC card defines a class, its responsibilities, and its collaborating classes.
• The classes that are discovered are,
  • Grade
  • Student
  • Course
  • Reportcard
• The purpose of the program is to generate a student report card.
• “student_id”, and “course_id” are the attributes of “Student” class.
• “grade” is not the attribute of the “Student” class.
• Just as in the printed report card, assume have a class “Grade” that records grades, and the grade point average.
• Make the report card responsible for formatting the report.
• Records that responsibility on a CRC card as follows,

Reportcard

format the report

• The report card format itself as follows,
  • It must format the student id, course id, format all grades, and then add grade point average,
  • The responsibility of “Student” class is to format student id, and this is the second CRC card,

Student

format the student id

• The report card also needs to calculate the grade point average.
• To get the grade, it should ask the Student about course id of each course.
• To get the grade point average, it should ask course for the grades.

Course

get the course_id get the grade

Grade
format the grade get grade point average	Course

• Finally, the report card should be populated with courses and grades, so that it makes sense to format the report. The final CRC card is as follows,

Reportcard
format the report add a grade and grade point average	Grade Student Course

UML diagram:

• In student report card, the “Student” class collaborates with the “Course” and “Reportcard” classes. The “Course” class collaborates with the “Grade” class.
• The “Student” class aggregates “Reportcard”, and “Course” classes.
• The “Course” class aggregates “Grade” class.
• The Unified Modeling Language (UML) diagram for the student report card is as follows,

“javadoc” comments:

A set of “javadoc” comment for the student report card is as follows,

/**

    Describes a student for a set of grades

*/

public class Student

{

    /**

         Add grades for a grade point average to this student...