Example usage for java.util Random Random

List of usage examples for java.util Random Random

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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:TestCipher.java

public static void main(String args[]) throws Exception {
    Set set = new HashSet();
    Random random = new Random();
    for (int i = 0; i < 10; i++) {
        Point point = new Point(random.nextInt(1000), random.nextInt(2000));
        set.add(point);/*from   w ww .ja v  a 2 s .  c  o  m*/
    }
    int last = random.nextInt(5000);

    // Create Key
    byte key[] = password.getBytes();
    DESKeySpec desKeySpec = new DESKeySpec(key);
    SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
    SecretKey secretKey = keyFactory.generateSecret(desKeySpec);

    // Create Cipher
    Cipher desCipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
    desCipher.init(Cipher.ENCRYPT_MODE, secretKey);

    // Create stream
    FileOutputStream fos = new FileOutputStream("out.des");
    BufferedOutputStream bos = new BufferedOutputStream(fos);
    CipherOutputStream cos = new CipherOutputStream(bos, desCipher);
    ObjectOutputStream oos = new ObjectOutputStream(cos);

    // Write objects
    oos.writeObject(set);
    oos.writeInt(last);
    oos.flush();
    oos.close();

    // Change cipher mode
    desCipher.init(Cipher.DECRYPT_MODE, secretKey);

    // Create stream
    FileInputStream fis = new FileInputStream("out.des");
    BufferedInputStream bis = new BufferedInputStream(fis);
    CipherInputStream cis = new CipherInputStream(bis, desCipher);
    ObjectInputStream ois = new ObjectInputStream(cis);

    // Read objects
    Set set2 = (Set) ois.readObject();
    int last2 = ois.readInt();
    ois.close();

    // Compare original with what was read back
    int count = 0;
    if (set.equals(set2)) {
        System.out.println("Set1: " + set);
        System.out.println("Set2: " + set2);
        System.out.println("Sets are okay.");
        count++;
    }
    if (last == last2) {
        System.out.println("int1: " + last);
        System.out.println("int2: " + last2);
        System.out.println("ints are okay.");
        count++;
    }
    if (count != 2) {
        System.out.println("Problem during encryption/decryption");
    }
}

From source file:Main.java

public static void main(String[] args) {
    JFrame frame = new JFrame();
    DrawPanel dp = new DrawPanel();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setContentPane(dp);/*from   w w  w.  ja v  a2s .c o m*/
    frame.pack();
    frame.setLocationByPlatform(true);
    try {
        Sequence seq = new Sequence(Sequence.PPQ, 4);
        Track track = seq.createTrack();
        for (int i = 0; i < 120; i += 4) {
            int d = (int) Math.abs(new Random().nextGaussian() * 24) + 32;
            track.add(makeEvent(ShortMessage.NOTE_ON, 1, d, 127, i));
            track.add(makeEvent(ShortMessage.CONTROL_CHANGE, 1, 127, 0, i));
            track.add(makeEvent(ShortMessage.NOTE_OFF, 1, d, 127, i));
        }
        Sequencer sequencer = MidiSystem.getSequencer();
        sequencer.open();
        sequencer.setSequence(seq);
        sequencer.addControllerEventListener(dp, new int[] { 127 });
        sequencer.start();
    } catch (Exception e) {
        e.printStackTrace();
    }
    frame.setVisible(true);
}

From source file:main.java.utils.Test.java

public static void main(String[] args) {

    Global.rand = new Random();
    Global.rand.setSeed(0);// w  w w  .  j a v a 2s  .  c o m

    for (int i = 0; i < 5; i++) {
        //System.out.println(RandomStringUtils.randomAlphanumeric(10));
        System.out.println(
                RandomStringGenerator.generateRandomString(10, RandomStringGenerator.Mode.ALPHANUMERIC));
    }
}

From source file:com.offbynull.peernetic.debug.visualizer.App.java

public static void main(String[] args) throws Throwable {
    Random random = new Random();
    Visualizer<Integer> visualizer = new JGraphXVisualizer<>();
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    Recorder<Integer> recorder = new XStreamRecorder(baos);

    visualizer.visualize(recorder, null);

    visualizer.step("Adding nodes 1 and 2", new AddNodeCommand<>(1),
            new ChangeNodeCommand(1, null, new Point(random.nextInt(400), random.nextInt(400)), Color.RED),
            new AddNodeCommand<>(2),
            new ChangeNodeCommand(2, null, new Point(random.nextInt(400), random.nextInt(400)), Color.BLUE));
    Thread.sleep(500);/* w w w. j  a v  a 2  s  .co m*/

    visualizer.step("Adding nodes 3 and 4", new AddNodeCommand<>(3),
            new ChangeNodeCommand(3, null, new Point(random.nextInt(400), random.nextInt(400)), Color.ORANGE),
            new AddNodeCommand<>(4),
            new ChangeNodeCommand(4, null, new Point(random.nextInt(400), random.nextInt(400)), Color.PINK));
    Thread.sleep(500);

    visualizer.step("Connecting 1/2/3 to 4", new AddEdgeCommand<>(1, 4), new AddEdgeCommand<>(2, 4),
            new AddEdgeCommand<>(3, 4));
    Thread.sleep(500);

    visualizer.step("Adding trigger to 4 when no more edges",
            new TriggerOnLingeringNodeCommand(4, new RemoveNodeCommand<>(4)));
    Thread.sleep(500);

    visualizer.step("Removing connections from 1 and 2", new RemoveEdgeCommand<>(1, 4),
            new RemoveEdgeCommand<>(2, 4));
    Thread.sleep(500);

    visualizer.step("Removing connections from 3", new RemoveEdgeCommand<>(3, 4));
    Thread.sleep(500);

    recorder.close();

    Thread.sleep(2000);

    JGraphXVisualizer<Integer> visualizer2 = new JGraphXVisualizer<>();
    ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray());
    Player<Integer> player = new XStreamPlayer<>(bais);

    visualizer2.visualize();

    player.play(visualizer2);

}

From source file:org.eclipse.swt.snippets.Snippet192.java

public static void main(String[] args) {
    // initialize data with keys and random values
    int size = 100;
    Random random = new Random();
    final int[][] data = new int[size][];
    for (int i = 0; i < data.length; i++) {
        data[i] = new int[] { i, random.nextInt() };
    }//from w  ww.j a  v  a  2  s. c o  m
    // create a virtual table to display data
    Display display = new Display();
    Shell shell = new Shell(display);
    shell.setText("Snippet 192");
    shell.setLayout(new FillLayout());
    final Table table = new Table(shell, SWT.VIRTUAL);
    table.setHeaderVisible(true);
    table.setLinesVisible(true);
    table.setItemCount(size);
    final TableColumn column1 = new TableColumn(table, SWT.NONE);
    column1.setText("Key");
    column1.setWidth(200);
    final TableColumn column2 = new TableColumn(table, SWT.NONE);
    column2.setText("Value");
    column2.setWidth(200);
    table.addListener(SWT.SetData, e -> {
        TableItem item = (TableItem) e.item;
        int index = table.indexOf(item);
        int[] datum = data[index];
        item.setText(new String[] { Integer.toString(datum[0]), Integer.toString(datum[1]) });
    });
    // Add sort indicator and sort data when column selected
    Listener sortListener = e -> {
        // determine new sort column and direction
        TableColumn sortColumn = table.getSortColumn();
        TableColumn currentColumn = (TableColumn) e.widget;
        int dir = table.getSortDirection();
        if (sortColumn == currentColumn) {
            dir = dir == SWT.UP ? SWT.DOWN : SWT.UP;
        } else {
            table.setSortColumn(currentColumn);
            dir = SWT.UP;
        }
        // sort the data based on column and direction
        final int index = currentColumn == column1 ? 0 : 1;
        final int direction = dir;
        Arrays.sort(data, (a, b) -> {
            if (a[index] == b[index])
                return 0;
            if (direction == SWT.UP) {
                return a[index] < b[index] ? -1 : 1;
            }
            return a[index] < b[index] ? 1 : -1;
        });
        // update data displayed in table
        table.setSortDirection(dir);
        table.clearAll();
    };
    column1.addListener(SWT.Selection, sortListener);
    column2.addListener(SWT.Selection, sortListener);
    table.setSortColumn(column1);
    table.setSortDirection(SWT.UP);
    shell.setSize(shell.computeSize(SWT.DEFAULT, SWT.DEFAULT).x, 300);
    shell.open();
    while (!shell.isDisposed()) {
        if (!display.readAndDispatch())
            display.sleep();
    }
    display.dispose();
}

From source file:stratego.neural.net.RandomSampleTest.java

public static void main(String[] args) {
    double[] wins = new double[data_points];
    double[] winrate = new double[data_points];
    List<double[]> data = new ArrayList<>();

    for (int i = 0; i < random.length; i++) {
        random[i] = new Random();
    }//from  www . j ava  2s .  c o  m

    for (int index = 0; index < repetitions; index++) {

        for (int i = 0; i < wins.length; i++) {
            wins[i] = (double) random[index].nextInt(2);
        }

        winrate[0] = wins[0];

        for (int i = 1; i < winrate.length; i++) {
            double total_wins = 0;
            for (int j = 0; j < i; j++) {
                total_wins = total_wins + wins[j];
            }
            winrate[i] = (total_wins / i);
        }

        data.add(winrate);
    }

    plotDataSet(data);
}

From source file:Snippet151.java

public static void main(String[] args) {
    final Display display = new Display();
    Shell shell = new Shell(display);
    shell.setLayout(new FillLayout());
    final Table table = new Table(shell, SWT.BORDER | SWT.VIRTUAL);
    table.addListener(SWT.SetData, new Listener() {
        public void handleEvent(Event e) {
            TableItem item = (TableItem) e.item;
            int index = table.indexOf(item);
            item.setText("Item " + data[index]);
        }/*from w w  w  .  j a  v  a2  s.c  o m*/
    });
    Thread thread = new Thread() {
        public void run() {
            int count = 0;
            Random random = new Random();
            while (count++ < 500) {
                if (table.isDisposed())
                    return;
                // add 10 random numbers to array and sort
                int grow = 10;
                int[] newData = new int[data.length + grow];
                System.arraycopy(data, 0, newData, 0, data.length);
                int index = data.length;
                data = newData;
                for (int j = 0; j < grow; j++) {
                    data[index++] = random.nextInt();
                }
                Arrays.sort(data);
                display.syncExec(new Runnable() {
                    public void run() {
                        if (table.isDisposed())
                            return;
                        table.setItemCount(data.length);
                        table.clearAll();
                    }
                });
                try {
                    Thread.sleep(500);
                } catch (Throwable t) {
                }
            }
        }
    };
    thread.start();
    shell.open();
    while (!shell.isDisposed() || thread.isAlive()) {
        if (!display.readAndDispatch())
            display.sleep();
    }
    display.dispose();
}

From source file:TableSortTwoDirection.java

public static void main(String[] args) {
    // initialize data with keys and random values
    int size = 100;
    Random random = new Random();
    final int[][] data = new int[size][];
    for (int i = 0; i < data.length; i++) {
        data[i] = new int[] { i, random.nextInt() };
    }//from  ww  w.  j  a  v  a 2  s .c o  m
    // create a virtual table to display data
    Display display = new Display();
    Shell shell = new Shell(display);
    shell.setLayout(new FillLayout());
    final Table table = new Table(shell, SWT.VIRTUAL);
    table.setHeaderVisible(true);
    table.setLinesVisible(true);
    table.setItemCount(size);
    final TableColumn column1 = new TableColumn(table, SWT.NONE);
    column1.setText("Key");
    column1.setWidth(200);
    final TableColumn column2 = new TableColumn(table, SWT.NONE);
    column2.setText("Value");
    column2.setWidth(200);
    table.addListener(SWT.SetData, new Listener() {
        public void handleEvent(Event e) {
            TableItem item = (TableItem) e.item;
            int index = table.indexOf(item);
            int[] datum = data[index];
            item.setText(new String[] { Integer.toString(datum[0]), Integer.toString(datum[1]) });
        }
    });
    // Add sort indicator and sort data when column selected
    Listener sortListener = new Listener() {
        public void handleEvent(Event e) {
            // determine new sort column and direction
            TableColumn sortColumn = table.getSortColumn();
            TableColumn currentColumn = (TableColumn) e.widget;
            int dir = table.getSortDirection();
            if (sortColumn == currentColumn) {
                dir = dir == SWT.UP ? SWT.DOWN : SWT.UP;
            } else {
                table.setSortColumn(currentColumn);
                dir = SWT.UP;
            }
            // sort the data based on column and direction
            final int index = currentColumn == column1 ? 0 : 1;
            final int direction = dir;
            Arrays.sort(data, new Comparator() {
                public int compare(Object arg0, Object arg1) {
                    int[] a = (int[]) arg0;
                    int[] b = (int[]) arg1;
                    if (a[index] == b[index])
                        return 0;
                    if (direction == SWT.UP) {
                        return a[index] < b[index] ? -1 : 1;
                    }
                    return a[index] < b[index] ? 1 : -1;
                }
            });
            // update data displayed in table
            table.setSortDirection(dir);
            table.clearAll();
        }
    };
    column1.addListener(SWT.Selection, sortListener);
    column2.addListener(SWT.Selection, sortListener);
    table.setSortColumn(column1);
    table.setSortDirection(SWT.UP);
    shell.setSize(shell.computeSize(SWT.DEFAULT, SWT.DEFAULT).x, 300);
    shell.open();
    while (!shell.isDisposed()) {
        if (!display.readAndDispatch())
            display.sleep();
    }
    display.dispose();
}

From source file:com.intuit.utils.PopulateUsers.java

public static void main(String[] args) {
    Date now = new Date();
    System.out.println("Current date is: " + now.toString());

    MongoClient mongo = new MongoClient("localhost", 27017);
    DB db = mongo.getDB("tweetsdb");
    DBCollection collection = db.getCollection("userscollection");
    WriteResult result = collection.remove(new BasicDBObject());

    int userIndex = 1;
    for (int i = 1; i <= 10; i++) {
        JSONObject userDocument = new JSONObject();
        String user = "user" + userIndex;
        userDocument.put("user", user);

        JSONArray followerList = new JSONArray();
        Random randomGenerator = new Random();
        for (int j = 0; j < 3; j++) {
            int followerId = randomGenerator.nextInt(10) + 1;
            // Assumption here is, a user will not be a follower on himself
            while (followerId == userIndex) {
                followerId = randomGenerator.nextInt(10) + 1;
            }/*from   w ww.j av  a  2 s. c o  m*/

            String follower = "user" + followerId;
            if (!followerList.contains(follower)) {
                followerList.add(follower);
            }
        }
        userDocument.put("followers", followerList);

        JSONArray followingList = new JSONArray();
        for (int k = 0; k < 3; k++) {
            int followingId = randomGenerator.nextInt(10) + 1;
            // Assumption here is, a user will not be following his own tweets
            while (followingId == userIndex) {
                followingId = randomGenerator.nextInt(10) + 1;
            }

            String followingUser = "user" + followingId;
            if (!followingList.contains(followingUser)) {
                followingList.add(followingUser);
            }
        }
        userDocument.put("following", followingList);
        System.out.println("Json string is: " + userDocument.toString());
        DBObject userDBObject = (DBObject) JSON.parse(userDocument.toString());
        collection.insert(userDBObject);
        userIndex++;

    }

    //        try {
    //            FileWriter file = new FileWriter("/Users/dmurty/Documents/MongoData/usersCollection.js");
    //            file.write(usersArray.toJSONString());
    //            file.flush();
    //            file.close();
    //        } catch (IOException ex) {
    //            Logger.getLogger(PopulateUsers.class.getName()).log(Level.SEVERE, null, ex);
    //        } 
}

From source file:main.java.entry.Main.java

public static void main(String[] args) throws IOException {
    Global.rand = new Random();
    Global.rdg = new RandomDataGenerator();

    Global.LOGGER.info("Simulating shared-nothing OLTP database cluster.");

    ReadConfig.readArgs(args);/* ww w.j a  v  a  2s.  co  m*/

    // Reading simulation aspects
    ReadConfig.readConfigFile("./sim.cnf");

    while (Global.repeatedRuns != 0) {

        Global.LOGGER.info("=============================================================================");
        Global.LOGGER.info("Starting simulation for run " + Global.repeatedRuns + " ...");

        // Re-seed the Random Data Generator
        Global.rand.setSeed(Global.repeatedRuns);
        Global.rdg.reSeed(Global.repeatedRuns);

        // Database initialization and population
        Database db = null;
        Workload wrl = null;

        switch (Global.wrl) {
        case "tpcc":
            db = new TpccDatabase("tpcc");
            wrl = new TpccWorkload("/tpcc.cnf");
            break;

        case "twitter":
            db = new TwitterDatabase("twitter");
            wrl = new TwitterWorkload("/twitter.cnf");
            break;

        default:
            Global.LOGGER.info(Global.run_usage);
            Global.LOGGER.info(Global.abort);
            break;
        }

        // CLuster, Workload Executor, and Metric Collector initialization
        Cluster dbCluster = new Cluster();
        WorkloadExecutor wrlExecutor = new WorkloadExecutor();
        Metric.init(dbCluster);

        // Read TPCC configurations
        wrl.readConfig();

        // Populate initial database                        
        db.populate(wrl);

        // Create a database cluster consisted of a set of physical servers and a consistent hash ring to store the physical data tuples
        WorkloadBatch wb = dbCluster.setup(db, wrl);

        // Workload execution
        wrlExecutor.execute(db, dbCluster, wb, wrl);

        // Close Metric collector
        Metric.close();

        // Proceed for the next iterative simulation run
        Global.LOGGER.info("Simulation ended for iterative run-" + Global.repeatedRuns + ".");
        --Global.repeatedRuns;
    }

    Global.LOGGER.info("Simulation ended.");
}