com.araguacaima.commons.utils.RandomUtils Maven / Gradle / Ivy

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package com.araguacaima.commons.utils;

import java.util.Random;

public class RandomUtils {

    private static final RandomUtils INSTANCE = new RandomUtils();
    ;

    private RandomUtils() {
        if (INSTANCE != null) {
            throw new IllegalStateException("Already instantiated");
        }
    }

    public static RandomUtils getInstance() {
        return INSTANCE;
    }

    public static double getRandomDoubleInRange(double aStart, double aEnd, Random aRandom) {
        if (aStart > aEnd) {
            throw new IllegalArgumentException("Start cannot exceed End.");
        }
        double range = aEnd - aStart + 1;
        double fraction = (range * aRandom.nextDouble());
        return (fraction + aStart);
    }

    public static long getRandomLongInRange(long aStart, long aEnd, Random aRandom) {
        if (aStart > aEnd) {
            throw new IllegalArgumentException("Start cannot exceed End.");
        }
        long range = aEnd - aStart + 1;
        long fraction = (long) (range * aRandom.nextDouble());
        return (fraction + aStart);
    }

    public Object clone() throws CloneNotSupportedException {
        throw new CloneNotSupportedException("Cannot clone instance of this class");
    }
}