CSC 217 Lab 06 Design
The design for Lab 06 is shown below. To follow the development paradigm of additive change, the course name validation functionality will be implemented in a new edu.ncsu.csc216.pack_scheduler.course.validator package. The only change to the remainder of the design occurs in the Course class, which now uses the CourseNameValidator to check for a valid course name as per the requirements.
The figure above is an example of a UML class diagram. Each class is represented by a rectangle; the text in the class describes the class members. Arrows indicate relationships between classes. The software used to generate the diagram in the figure uses the following notation conventions:
- A square (empty or solid) in front of a name means private. Solid squares are operations, empty squares are data.
- A green circle in front of a name means public. Solid circles are operations, empty circles are data.
- Members embellished with S are static.
- Members embellished with SF are static, final. (
Course.MAX_CREDITSis public, static, and final.) - Methods embellished with C are constructors. (See
Course.Course().) - Solid arrows with simple heads indicate has-a relationships, in which one class has a member whose type is another class or interface. The containing class is at the tail of the arrow and the class that is contained is at the head. The arrow is decorated with the name and access of the member in the containing class (- for private, + for public). The arrow is also decorated with the “multiplicity” of the relationship, where 0..1 means there is 1 instance of the member in the containing class and 0..* means there are many, usually indicating a collection such as an array. (
Coursehas a private member namedvalidatorthat is aCourseNameValidator.) - The connector with a circle containing a cross indicates an inner class relationship. The class with the crossed circle is the enclosing class and the other class is the inner class. (
LetterStateis an inner class ofState).
The following sections will provide details about how to implement the changes to the design.