Example usage for java.util Random nextInt

Introduction

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

Prototype

public int nextInt(int bound)

Source Link

Document

Returns a pseudorandom, uniformly distributed int value between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence.

Usage

From source file:com.betfair.application.performance.BaselinePerformanceTester.java

private static HttpCallable getRequest(Random rnd) {
    return requests.getValue(rnd.nextInt(requests.getMaxRange()));
}

From source file:com.infovity.iep.loader.util.SupplierLoaderUtil.java

public static int gen() {
    Random r = new Random(System.currentTimeMillis());
    return ((1 + r.nextInt(2)) * 10000 + r.nextInt(10000));
}

From source file:com.betfair.application.performance.BaselinePerformanceTester.java

private static String getContentType(Random rnd) {
    return protocols.getValue(rnd.nextInt(protocols.getMaxRange()));
}

From source file:fastcall.FArrayUtils.java

/**
 * Shuffle an int array//ww  w .  j  a  va  2 s  . c  o  m
 * Implementing FisherYates shuffle
 * @param ar 
 */
public static void shuffleArray(int[] ar) {
    Random rnd = new Random();
    for (int i = ar.length - 1; i > 0; i--) {
        int index = rnd.nextInt(i + 1);
        // Simple swap
        int a = ar[index];
        ar[index] = ar[i];
        ar[i] = a;
    }
}

From source file:fastcall.FArrayUtils.java

/**
 * Shuffle an double array/* w w  w  .j  ava2s.co  m*/
 * Implementing FisherYates shuffle
 * @param ar 
 */
public static void shuffleArray(double[] ar) {
    Random rnd = new Random();
    for (int i = ar.length - 1; i > 0; i--) {
        int index = rnd.nextInt(i + 1);
        // Simple swap
        double a = ar[index];
        ar[index] = ar[i];
        ar[i] = a;
    }
}

From source file:com.liferay.portal.security.pwd.PwdEncryptor.java

private static byte[] _getSaltFromCrypt(String cryptString) throws PwdEncryptorException {

    byte[] saltBytes = null;

    try {//w w  w  .ja  v  a 2 s  . c o  m
        //if (Validator.isNull(cryptString)) {
        if (StringUtils.isEmpty(cryptString)) {

            // Generate random salt

            Random random = new Random();

            int numSaltChars = saltChars.length;

            StringBuilder sb = new StringBuilder();

            int x = random.nextInt(Integer.MAX_VALUE) % numSaltChars;
            int y = random.nextInt(Integer.MAX_VALUE) % numSaltChars;

            sb.append(saltChars[x]);
            sb.append(saltChars[y]);

            String salt = sb.toString();

            //saltBytes = salt.getBytes(Digester.ENCODING);
            saltBytes = salt.getBytes("UTF8");
        } else {

            // Extract salt from encrypted password

            String salt = cryptString.substring(0, 2);

            //saltBytes = salt.getBytes(Digester.ENCODING);
            saltBytes = salt.getBytes("UTF8");
        }
    } catch (UnsupportedEncodingException uee) {
        throw new PwdEncryptorException("Unable to extract salt from encrypted password: " + uee.getMessage());
    }

    return saltBytes;
}

From source file:net.sf.javaml.tools.DatasetTools.java

/**
 * Generate a bootstrap sample from the data set with a particular size,
 * using the given random generator./*ww w.  j a v a 2s .  co m*/
 * 
 * This is done by sampling with replacement.
 * 
 * @param data
 *            data set to bootstrap from
 * @param size
 *            number of instances in the output data
 * @param rg
 *            random generator to use for the bootstrapping
 * @return bootstrap of the supplied data
 */
@Deprecated
public static Dataset bootstrap(Dataset data, int size, Random rg) {
    Dataset out = new DefaultDataset();
    while (out.size() < size) {
        out.add(data.instance(rg.nextInt(data.size())).copy());
    }
    return out;
}

From source file:com.feilong.commons.core.util.StringUtilTest.java

/**
 * ?150?.//from  w  ww. j  a  va 2  s  .c o m
 * 
 * @return the random string
 */
private static String getRandomString() {
    StringBuilder sb = new StringBuilder();
    Random r = new Random();
    int length = 150 + r.nextInt(50);
    for (int i = 0; i < length; i++) {
        sb.append('a' + r.nextInt(26));
    }
    return sb.toString();
}

From source file:com.espertech.esper.epl.variable.VariableServiceCallable.java

private static int[] getIndexesShuffled(int length, Random random, int loopNum) {
    int[] indexRandomized = new int[length];

    for (int i = 0; i < indexRandomized.length; i++) {
        indexRandomized[i] = i;// w  ww .  ja  v  a  2s.c  o  m
    }

    for (int i = 0; i < length; i++) {
        int indexOne = random.nextInt(length);
        int indexTwo = random.nextInt(length);
        int temp = indexRandomized[indexOne];
        indexRandomized[indexOne] = indexRandomized[indexTwo];
        indexRandomized[indexTwo] = temp;
    }

    return indexRandomized;
}

From source file:Main.java

/**
 * Fills the array with random longs.  If signed is true, negative values can be generated.
 * The values will fit within 'numberOfBits'.  This is useful for conversion tests.
 *///from w  w  w  .  j a v  a 2  s  .  com
public static void genRandomLongs(long seed, long array[], boolean signed, int numberOfBits) {
    long positiveMask = numberOfBits == 64 ? -1 : ((1l << numberOfBits) - 1);
    long negativeMask = ~positiveMask;
    Random r = new Random(seed);
    for (int i = 0; i < array.length; i++) {
        long l = r.nextLong();
        if (signed && l < 0) {
            l = l | negativeMask;
        } else {
            l = l & positiveMask;
        }
        array[i] = l;
    }
    // Seed a few special numbers we want to be sure to test.
    array[r.nextInt(array.length)] = 0l;
    array[r.nextInt(array.length)] = 1l;
    array[r.nextInt(array.length)] = positiveMask;
    if (signed) {
        array[r.nextInt(array.length)] = negativeMask;
        array[r.nextInt(array.length)] = -1;
    }
}