Example usage for java.util Collections shuffle

Introduction

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

Prototype

public static void shuffle(List<?> list)

Source Link

Document

Randomly permutes the specified list using a default source of randomness.

Usage

From source file:com.shirokumacafe.archetype.common.utilities.RandomData.java

/**
 * list?n.//from www.j av a  2s. c o m
 */
public static <T> List<T> randomSome(List<T> list, int n) {
    Collections.shuffle(list);
    return list.subList(0, n);
}

From source file:com.ijuru.ijambo.Utils.java

/**
 * Scrambles the letters of a word. Shuffles the word twice and returns
 * the result with the highest levenshtein distance from the original
 * @param word the word//from   w ww. j a v  a2  s.c om
 * @return the scrambled word
 */
public static String scrambleWord(String word) {
    List<String> chars1 = Arrays.asList(word.split(""));
    List<String> chars2 = new ArrayList<String>(chars1);

    Collections.shuffle(chars1);
    Collections.shuffle(chars2);

    String scramble1 = StringUtils.join(chars1, "");
    String scramble2 = StringUtils.join(chars2, "");

    int dist1 = StringUtils.getLevenshteinDistance(word, scramble1);
    int dist2 = StringUtils.getLevenshteinDistance(word, scramble2);

    return (dist1 > dist2) ? scramble1 : scramble2;
}

From source file:Main.java

/**
 * This method generates a random n digit password, which contains at least one number, lower case alphabet, upper
 * case alphabet and as special character.
 *//*from w ww  .j a v  a 2s  .  c  om*/
public static String generatePassword(int n) {

    Random rd = new Random();

    char lowerChars[] = "abcdefghijklmnopqrstuvwxyz".toCharArray();
    char upperChars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();
    char numbers[] = "0123456789".toCharArray();
    char specialChars[] = "~!@#$%^&*()-_=+[{]}|;:<>/?".toCharArray();

    List<Character> pwdLst = new ArrayList<Character>();
    for (int g = 0; g < 4; g++) {
        for (int z = 0; z < 1; z++) {
            if (g == 0) {
                pwdLst.add(numbers[rd.nextInt(10)]);
            } else if (g == 1) {
                pwdLst.add(lowerChars[rd.nextInt(26)]);
            } else if (g == 2) {
                pwdLst.add(upperChars[rd.nextInt(26)]);
            } else if (g == 3) {
                pwdLst.add(specialChars[rd.nextInt(26)]);
            }
        }
        if (pwdLst.size() == n) {
            break;
        }
        if (g + 1 == 4) {
            g = (int) Math.random() * 5;

        }
    }
    StringBuilder password = new StringBuilder();
    Collections.shuffle(pwdLst);
    for (int c = 0; c < pwdLst.size(); c++) {
        password.append(pwdLst.get(c));
    }
    return password.toString();
}

From source file:com.dianping.dpsf.other.echo.SimpleEchoClient.java

private static List<String[]> generateHostList() {
    List<String[]> hostList = new ArrayList<String[]>();
    hostList.add(new String[] { "127.0.0.1", "20001" });
    hostList.add(new String[] { "127.0.0.1", "20002" });
    hostList.add(new String[] { "127.0.0.1", "20003" });

    Random rnd = new Random(System.currentTimeMillis());
    int num = rnd.nextInt(3) + 1;
    Collections.shuffle(hostList);
    return hostList.subList(0, num);
}

From source file:com.stb.async.EncodedSTBProcesses.java

/**
 *
 * @param range/*from   w ww . j a v  a  2s.  com*/
 * @param total_processes
 * @return
 */
public List initiateProcess(int total_processes, int range) {

    ArrayList<Integer> numbers = new ArrayList<>();
    for (int i = 0; i < range; i++) {
        numbers.add(i + 1);
    }

    Collections.shuffle(numbers);
    for (int j = 0; j < total_processes; j++) {
        System.out.print(numbers.get(j) + " ");
        procList.add(new Process("Process P" + numbers.get(j) + " .", numbers.get(j)));
    }

    return procList;

}

From source file:edu.eci.arsw.blindway.mazegenerator.RecursiveMazeGenerator.java

private void generateMaze(int cx, int cy) {
    DIR[] dirs = DIR.values();/*from  www . j  av a  2s . c  o  m*/
    Collections.shuffle(Arrays.asList(dirs));
    for (DIR dir : dirs) {
        int nx = cx + dir.dx;
        int ny = cy + dir.dy;
        if (between(nx, x) && between(ny, y) && (maze[nx][ny] == 0)) {
            maze[cx][cy] |= dir.bit;
            maze[nx][ny] |= dir.opposite.bit;
            generateMaze(nx, ny);
        }
    }
}

From source file:edu.isi.pfindr.learn.util.PairsFileIO.java

@SuppressWarnings("unchecked")
public static void shuffler(String pairsFilename) throws IOException {
    List<String> fileWithPairs = FileUtils.readLines(new File(pairsFilename));
    Collections.shuffle(fileWithPairs);
    String outputFilename = pairsFilename.split("\\.")[0] + "_s.txt"; //output filename derived from the pairs filename
    FileUtils.writeLines(new File(outputFilename), fileWithPairs);
}

From source file:Main.java

public RandomIterator(final Iterator<T> i) {
    final List<T> items;

    items = new ArrayList<T>();

    while (i.hasNext()) {
        final T item;

        item = i.next();/*from ww  w.j a va 2 s  . c  om*/
        items.add(item);
    }

    Collections.shuffle(items);
    iterator = items.iterator();
}

From source file:com.joyent.manta.client.MantaObjectDepthComparatorTest.java

public void verifyOrderingWithSmallDataSet() {
    List<MantaObject> objects = new ArrayList<>();
    List<MantaObject> dirs = dirObjects(12);

    for (MantaObject dir : dirs) {
        objects.add(dir);//from   w w  w.j ava 2 s .  c  o  m
        objects.addAll(fileObjects(dir, 3));
    }

    Collections.shuffle(objects);

    objects.sort(MantaObjectDepthComparator.INSTANCE);

    assertOrdering(objects);
}

From source file:common.Utilities.java

public static List<Integer> getRandomIndices(int from, int to) {
    List<Integer> indices = new ArrayList<Integer>();
    for (int j = from; j <= to; j++) {
        indices.add(j);/*w  ww  . j  a  va2  s .c o m*/
    }
    Collections.shuffle(indices);
    return indices;
}