Example usage for java.util Random Random

Introduction

In this page you can find the example usage for java.util Random Random.

Prototype

public Random()

Source Link

Document

Creates a new random number generator.

Usage

From source file:Main.java

public static String getNumberRadim(int n) {
    if (n < 1 || n > 10) {
        throw new IllegalArgumentException("cannot random " + n + " bit number");
    }//www  .j a  v a  2s  . c o m
    Random ran = new Random();
    if (n == 1) {
        return String.valueOf(ran.nextInt(10));
    }
    int bitField = 0;
    char[] chs = new char[n];
    for (int i = 0; i < n; i++) {
        while (true) {
            int k = ran.nextInt(10);
            if ((bitField & (1 << k)) == 0) {
                bitField |= 1 << k;
                chs[i] = (char) (k + '0');
                break;
            }
        }
    }
    return new String(chs);
}

From source file:Main.java

public static String get_random_motivation_message() {
    int idx = new Random().nextInt(mm.length);
    return (mm[idx]);
}

From source file:Main.java

public static ArrayList<Integer> shuffleArray(int size) {
    ArrayList<Integer> shuffled = new ArrayList<>();
    for (int i = 0; i < size; i++) {
        shuffled.add(i);/*from  ww w .j  a v a 2  s  . c om*/
    }

    Random rnd = new Random();
    for (int i = size - 1; i > 0; i--) {
        int index = rnd.nextInt(i + 1);
        // Simple swap
        int a = shuffled.get(index);
        shuffled.set(index, shuffled.get(i));
        shuffled.set(i, a);
    }

    return shuffled;
}

From source file:Main.java

public static String generateFileName(String fileName) {
    DateFormat format = new SimpleDateFormat("yyMMddHHmmss");
    String formatDate = format.format(new Date());
    int random = new Random().nextInt(10000);
    int position = fileName.lastIndexOf(".");
    String extension = fileName.substring(position);

    return formatDate + random + extension;
}

From source file:Main.java

public static double getRandomNumber(double start, double end) {
    double random = new Random().nextDouble();
    double result = start + (random * (end - start));
    return result;
}

From source file:Main.java

public static int nextInt(int lower, int upper) {
    Random ra = new Random();
    return (lower + ra.nextInt(upper - lower + 1));
}

From source file:Main.java

/**
 * Get a random number within a given upper limit;
 *//*from w w  w  . ja  va2s .c  o m*/
public static int getRandomInt(int max) throws Exception {
    int ret;
    Random r = new Random();
    ret = r.nextInt(max);

    Log.i(TAG, String.format("Generate an integer value: %d", ret));

    return ret;
}

From source file:Main.java

/**
 * Returns a valid IP v4 address.//from ww  w .j a va 2s . c om
 *
 * @return [0-255].[0-255].[0-255].[0-255]
 */
public static String generateRandomIp() {
    try {
        Random r = new Random();
        String ip = r.nextInt(256) + "." + r.nextInt(256) + "." + r.nextInt(256) + "." + r.nextInt(256);
        if (isValidIp(ip)) {
            return ip;
        } else {
            return generateRandomIp();
        }
    } catch (Exception e) {
    }
    return "127.0.0.1";
}

From source file:Main.java

public static String getRandomString(int length) {
    if (length <= 0)
        return null;

    StringBuffer sb = new StringBuffer();
    Random r = new Random();
    int range = RANDOM_CHARS.length();
    for (int i = 0; i < length; i++) {
        sb.append(RANDOM_CHARS.charAt(r.nextInt(range)));
    }/*from w w  w.  j a v a 2 s .com*/
    return sb.toString();
}

From source file:Main.java

static String generateHoodieId() {
    int hoodieIDLength = 7;
    String alphabet = "0123456789abcdefghijklmnopqrstuvwxyz";
    int alphabetLength = alphabet.length();

    String result = "";

    Random rnd = new Random();

    for (int i = 0; i < hoodieIDLength; i++) {
        int r = rnd.nextInt(alphabetLength);
        char c = alphabet.charAt(r);

        result += c;/*from w  ww  . j av  a  2  s  .co  m*/
    }

    return result;
}