Triangle Class

Semiperimeter, what is that?

The semiperimeter is just ½ the perimeter of a triangle (it is denoted by the letter s; s = ½(a+b+c)). Besides just being a really nice proof (because all computer scientist also loves math!), it is actually useful to calculate the area of a triangle. Normally we use the formula (A = ½ bh). But in a lot of triangles, we do not know what the height is and don’t want to calculate it; we only know the length of the three sides. It can be proven (using Heron's formula) that the area of a triangle can also be calculated using:

Here is the problem

Create a program that lets the user enter any combination of 3 pieces of information about a triangle (side length or angle) but not 3 angles. The user can then display information about the area, perimeter, and type. Since the application is about triangles, which have a clear set of related calculations and properties, a Triangle class will be implemented. It will have at least the following:

• private data members (fields)
• 1 constructor (because when you create a triangle, the user will provide 3 pieces of information)
• 1 protected function (IsTriangleValid)
• 2 public function (GetArea, GetName)

Two part assignment

This is a 2-week assignment:

• Week 1 hand in DESIGN ONLY
  • Top-down, class diagram and a flowchart for each method (but not pseudo-code) and test cases (make sure you cover every possibility this time!)
• Week 2 hand in EVERYTHING ELSE
  • plus the stuff from part a

Each week ENSURE you include the Marking Rubric

Things to note

• If you are not sure on any part of the problem, just ask me and I will give you additional information
• You must do the program in Java first (get a 3+).
• Remember create you class diagram first. All of the brains for the program must be in the class; the program is just a stub to use the class. It should only be checking for valid input from the “village idiot” and accepting or rejecting it.
• Higher mark
  • Get a 4- if you can create another method that calculates the height of the triangle
  • Get a 4* if you can calculate the radius of the largest inscribed circle that can fit inside the triangle:

• Get a 4+ if you do the above BUT ALSO calculate the area of the Circumcircle of the triangle:

• See Marking Rubric below
• Ensure you work through (in order):
  • Class diagram(s)
  • Flow-chart(s), for each method in the class diagram
  • Test cases
  • Final, debugged, commented code
  • Screenshots proving test cases are correct
• Ensure you follow the "Hand in Process"