Example usage for java.lang Math random

Introduction

In this page you can find the example usage for java.lang Math random.

Prototype

public static double random()

Source Link

Document

Returns a double value with a positive sign, greater than or equal to 0.0 and less than 1.0 .

Usage

From source file:Main.java

public static int getRandomNum(int maxNum) {
    return (int) (Math.random() * maxNum);
}

From source file:Main.java

public static String randomString(int len, String charset) {
    String out = "";

    for (int i = 0; i < len; i++) {
        out += charset.charAt((int) (Math.random() * charset.length()));
    }//from w ww. j  a  v a  2 s . c  o  m

    return out;
}

From source file:Main.java

public static List<String> populateStringList(int numberOfItems) {
    final String partialWord = "partialListParallel";
    List<String> dummyStringList = null;
    if (numberOfItems > 0) {
        dummyStringList = new ArrayList<String>();
        for (int i = 0; i < numberOfItems; i++) {
            final double randomNumber = (Math.random() * numberOfItems);
            final StringBuilder sb = new StringBuilder(partialWord).append(randomNumber);
            dummyStringList.add(sb.toString());
        }//from  w w w  .  j a  va  2  s . c o m
    }
    return dummyStringList;
}

From source file:Main.java

public static String getRandomString(int length) {
    Random random = new Random();
    StringBuffer sb = new StringBuffer();
    for (int i = 0; i < length; i++) {
        int number = random.nextInt(3);
        long result = 0;
        switch (number) {
        case 0:/*  w  w  w. java 2s  .co  m*/
            result = Math.round(Math.random() * 25 + 65);
            sb.append(String.valueOf((char) result));
            break;
        case 1:
            result = Math.round(Math.random() * 25 + 97);
            sb.append(String.valueOf((char) result));
            break;
        case 2:
            sb.append(String.valueOf(new Random().nextInt(10)));
            break;
        }

    }
    return sb.toString();
}

From source file:Main.java

public static Employee employeeMaker() {
    List<String> names = Arrays.asList("John Doe", "Jane Doe", "Mark Twain", "Oliver Twist", "Ferdinand IV");

    return new Employee(names.get((int) (Math.random() * names.size())), Math.random() * 20_000);
}

From source file:Main.java

private static String getSessionComponent() {
    return Integer.toHexString((int) ((Math.random() + 1) * 0x10000)).substring(1);
}

From source file:Main.java

public static Uri getRandomRingtone(Context context) {
    Uri alert = null;/*w  ww  .ja v a  2 s.c  om*/
    RingtoneManager ringtoneManager = new RingtoneManager(context);
    ringtoneManager.setType(RingtoneManager.TYPE_ALARM);
    int count = ringtoneManager.getCursor().getCount();
    int attempts = 0;
    do {
        int random = (int) Math.random() * (count + 1);
        alert = ringtoneManager.getRingtoneUri(random);
    } while (alert == null && ++attempts < 5);
    return alert;
}

From source file:Main.java

public static int randomInt(int upto) {

    int number;//w  w  w . j a v  a  2 s. co  m

    number = (int) Math.floor(Math.random() * upto);

    return number;
}

From source file:Main.java

public static Color getRandColor(int threashold) {
    if (threashold < 0 || threashold > 255)
        throw new IllegalArgumentException("Threashold is not between 0 and 255");
    int secondOperand = 255 - threashold;
    return new Color((int) (Math.random() * secondOperand) + threashold,
            (int) (Math.random() * secondOperand) + threashold,
            (int) (Math.random() * secondOperand) + threashold);
}

From source file:Main.java

/** Returns a random value in the range [1 - range] */
public static long random(long range) {
    return (long) ((Math.random() * range) % range) + 1;
}