Thread: What does this question mean?

So this is my assignment and I am having trouble trying to understand this question in part a, basically the part b is calculating area of a triangle which is tied up with the part a, the main issue is that I have declared the double variable for a,b and c but the logic of settng the sides and then making sure that the sum of any two sides should be greater than the third one. How to do this?

(a) Write a Java class InvalidValueException. Objects of this class, when created, will
show a simple message informing you of the nature of the exception thrown.

(b) Given three straight lines a, b & c. They will be able to form a triangle provided that sum
of any two lines is always greater than the third line (i.e. a + b > c and b + c > a and a + c
> b).
Write a Java class Triangle with the following:
„h Attributes: length of the three sides of the triangle
„h Behaviour:
- Constructor that sets the length of the three sides to the values passed in. The
constructor should throw an InvalidValueException object when the values
are not able to form a triangle.
- findArea() method to calculate the area of the Triangle object using the
formula
area = s * (s ƒ{ a) * (s ƒ{ b) * (s ƒ{ c) where s =
2
a ƒy b ƒy c