8Ball (with solution)

The idea behind an 8-Ball is very simple. You ask the eight ball a yes or no question, and it tells you the answer.

Except, that the answer it choses is randomly selected from a set of prefabricated responses.

A real life 8-Ball

Write a program that continuously prompts the user for a yes or no question, and then randomly selects from 5 canned answers:

• Without a doubt.
• Yes.
• Ask again later.
• No.
• Karel thinks so.

Here is an example run of the program.

To generate random numbers create a RandomGenerator instance variable (a variable declared outside all methods) like so:

You can then use the variable to generate random numbers.

Solution

/**
 * Class: Eight Ball
 * -----------------
 * Simulates an eight ball and gives sage answers to yes or
 * no questions.
 */
public class EightBall extends ConsoleProgram {
	
	private static RandomGenerator rg = new RandomGenerator();
	
	public void run() {
		while(true) {
			readLine("Ask a yes or no question: ");
			
			int choice = rg.nextInt(5);
			println(choice);
			if(choice == 0) {
				println("Without a doubt");
			}
			if(choice == 1) {
				println("Yes");
			}
			if(choice == 2) {
				println("Ask again later.");
			}
			if(choice == 3) {
				println("No");
			}
			if(choice == 4) {
				println("Karel thinks so.");
			}
			println("");
		}
	}
}