A Problem Solved: Representing Coins

Problem statement

Imagine that we need to represent coins in various programs. A coin has two sides, heads and tails. Additionally, a coin has a monetary value and shows the year in which it was minted. Let’s decide that these characteristics are sufficient for our purposes and create a class of coins.

Designing the class

We’ll name the class Coin and give it four data fields, as follows:

• sideUp—a designation for heads or tails
• name—the coin’s name as a string
• value—a representation of the coin’s value
• year—a positive integer denoting the year the coin was minted

Let’s also give the class the following methods:

• Accessor methods that return the coin’s visible side—heads or tails—its name, its value in cents, and its mint year
• Boolean-valued methods that test whether the coin’s visible side is heads or tails
• A method that simulates a coin toss by assigning a designation for heads or tails to sideUp at random
• The method toString

After naming these methods and refining their specifications, we can write the following comments and method headers:

/** Returns the string "HEADS" if the coin is heads side

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