// arrays/IceCream.java // (c)2016 MindView LLC: see Copyright.txt // We make no guarantees that this code is fit for any purpose. // Visit http://mindviewinc.com/Books/OnJava/ for more book information. // Returning arrays from methods import java.util.*; import static onjava.ArrayShow.*; public class IceCream { private static SplittableRandom rand = new SplittableRandom(47); static final String[] FLAVORS = { "Chocolate", "Strawberry", "Vanilla Fudge Swirl", "Mint Chip", "Mocha Almond Fudge", "Rum Raisin", "Praline Cream", "Mud Pie" }; public static String[] flavorSet(int n) { if(n > FLAVORS.length) throw new IllegalArgumentException("Set too big"); String[] results = new String[n]; boolean[] picked = new boolean[FLAVORS.length]; for(int i = 0; i < n; i++) { int t; do t = rand.nextInt(FLAVORS.length); while(picked[t]); results[i] = FLAVORS[t]; picked[t] = true; } return results; } public static void main(String[] args) { for(int i = 0; i < 7; i++) show(flavorSet(3)); } } /* Output: [Rum Raisin, Mint Chip, Mocha Almond Fudge] [Chocolate, Strawberry, Mocha Almond Fudge] [Strawberry, Mint Chip, Mocha Almond Fudge] [Rum Raisin, Vanilla Fudge Swirl, Mud Pie] [Vanilla Fudge Swirl, Chocolate, Mocha Almond Fudge] [Praline Cream, Strawberry, Mocha Almond Fudge] [Mocha Almond Fudge, Strawberry, Mint Chip] */