Example usage for java.util Random setSeed

Introduction

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

Prototype

public synchronized void setSeed(long seed) 

Source Link

Document

Sets the seed of this random number generator using a single long seed.

Usage

From source file:Main.java

public static void main(String args[]) {

    Random randomno = new Random();

    // setting seed
    randomno.setSeed(20);

    // value after setting seed
    System.out.println("Object after seed: " + randomno.nextInt());
}

---

From source file:org.apache.hadoop.hbase.regionserver.TestPerColumnFamilyFlush.java

public static void main(String[] args) throws Exception {
    int numRegions = Integer.parseInt(args[0]);
    long numRows = Long.parseLong(args[1]);

    HTableDescriptor htd = new HTableDescriptor(TABLENAME);
    htd.setMaxFileSize(10L * 1024 * 1024 * 1024);
    htd.setValue(HTableDescriptor.SPLIT_POLICY, ConstantSizeRegionSplitPolicy.class.getName());
    htd.addFamily(new HColumnDescriptor(FAMILY1));
    htd.addFamily(new HColumnDescriptor(FAMILY2));
    htd.addFamily(new HColumnDescriptor(FAMILY3));

    Configuration conf = HBaseConfiguration.create();
    Connection conn = ConnectionFactory.createConnection(conf);
    Admin admin = conn.getAdmin();/*  ww  w  . j a  va  2 s. c om*/
    if (admin.tableExists(TABLENAME)) {
        admin.disableTable(TABLENAME);
        admin.deleteTable(TABLENAME);
    }
    if (numRegions >= 3) {
        byte[] startKey = new byte[16];
        byte[] endKey = new byte[16];
        Arrays.fill(endKey, (byte) 0xFF);
        admin.createTable(htd, startKey, endKey, numRegions);
    } else {
        admin.createTable(htd);
    }
    admin.close();

    Table table = conn.getTable(TABLENAME);
    byte[] qf = Bytes.toBytes("qf");
    Random rand = new Random();
    byte[] value1 = new byte[16];
    byte[] value2 = new byte[256];
    byte[] value3 = new byte[4096];
    for (long i = 0; i < numRows; i++) {
        Put put = new Put(Hashing.md5().hashLong(i).asBytes());
        rand.setSeed(i);
        rand.nextBytes(value1);
        rand.nextBytes(value2);
        rand.nextBytes(value3);
        put.addColumn(FAMILY1, qf, value1);
        put.addColumn(FAMILY2, qf, value2);
        put.addColumn(FAMILY3, qf, value3);
        table.put(put);
        if (i % 10000 == 0) {
            LOG.info(i + " rows put");
        }
    }
    table.close();
    conn.close();
}

---

From source file:com.openteach.diamond.network.waverider.network.Packet.java

public static void main(String[] args) {
    /*System.out.println("[DEBUG] Packet Header size = " + getHeaderSize());
            //from   w  w  w  .j  a v  a  2 s  .  com
    SlaveState slaveState = new SlaveState();
    slaveState.setId(1L);
    slaveState.setIsMasterCandidate(false);
    Command command = CommandFactory.createHeartbeatCommand(slaveState.toByteBuffer());
    Packet packet = Packet.newDataPacket(command);
    ByteBuffer buffer = packet.marshall();
    Packet p = Packet.unmarshall(buffer);
    Command cmd = Command.unmarshall(p.getPayLoad());
    SlaveState ss = SlaveState.fromByteBuffer(cmd.getPayLoad());
    System.out.println(cmd.toString());
            
            
    // Test 2
    MasterState masterState = new MasterState();
    masterState.setId(1L);
    masterState.setIp("127.0.0.1");
    masterState.setPort(8206);
    List<SessionState> sessionStateList = new LinkedList<SessionState>();
    masterState.setSessionStateList(sessionStateList);
    SessionState sessionState = null;
    for(int i = 0; i < 10; i++) {
       sessionState = new SessionState();
       sessionState.setIp("127.0.0.1");
       sessionState.setPriority(1L);
       sessionState.setIsMasterCandidate(false);
       sessionStateList.add(sessionState);
    }
    Command command2 = CommandFactory.createHeartbeatCommand(masterState.toByteBuffer());
    Packet packet2 = Packet.newDataPacket(command2);
    ByteBuffer buffer2 = packet2.marshall();
    Packet p2 = Packet.unmarshall(buffer2);
    Command cmd2 = Command.unmarshall(p2.getPayLoad());
    MasterState ms = MasterState.fromByteBuffer(cmd2.getPayLoad());
    System.out.println(cmd.toString());
    */

    System.out.println("[DEBUG] Packet Header size = " + getHeaderSize());

    BlockingQueue<ByteBuffer> queue = new LinkedBlockingQueue<ByteBuffer>();
    Random rand = new Random();
    int count = 0;
    int size = 0;
    for (int i = 0; i < 100000; i++) {
        SlaveState state = new SlaveState();
        state.setId(Long.valueOf(i));
        state.setIsMasterCandidate(true);
        Packet packet = Packet.newDataPacket(
                CommandFactory.createCommand(Command.AVAILABLE_COMMAND_START, state.toByteBuffer()));
        ByteBuffer buffer = packet.marshall();
        rand.setSeed(System.currentTimeMillis());
        count = rand.nextInt(100) + 1;
        size = buffer.remaining() / count;
        for (int j = 0; j < count; j++) {
            ByteBuffer buf = null;
            if (j == count - 1) {
                buf = ByteBuffer.allocate(buffer.remaining() - j * size);
                buf.put(buffer.array(), j * size, buffer.remaining() - j * size);
            } else {
                buf = ByteBuffer.allocate(size);
                buf.put(buffer.array(), j * size, size);
            }
            buf.flip();
            queue.add(buf);
        }
    }

    for (int i = 0; i < 100000; i++) {
        //Packet packet = Packet.parse(queue);
        //Command commad = Command.unmarshall(packet.getPayLoad());
        //SlaveState state = SlaveState.fromByteBuffer(commad.getPayLoad());
        //System.out.println(state.toString());
    }
}

---

From source file:Main.java

public static long initRandomSerial() {
    final Random rnd = new Random();
    rnd.setSeed(System.currentTimeMillis());
    // prevent browser certificate caches, cause of doubled serial numbers
    // using 48bit random number
    long sl = ((long) rnd.nextInt()) << 32 | (rnd.nextInt() & 0xFFFFFFFFL);
    // let reserve of 16 bit for increasing, serials have to be positive
    sl = sl & 0x0000FFFFFFFFFFFFL;/*  w  w w  .  ja  va  2s .co m*/
    return sl;
}

---

From source file:Main.java

public static String generatePassword() {
    Random r[] = new Random[8];
    r[0] = new Random();
    r[1] = new Random();
    r[2] = new Random();
    r[3] = new Random();
    r[4] = new Random();
    r[5] = new Random();
    r[6] = new Random();
    r[7] = new Random();
    Random x = new Random();
    StringBuilder password = new StringBuilder();
    int length = 6;
    password.setLength(length);//w w  w. j  a v  a  2s .c o m
    for (int i = 0; i < length; i++) {
        x.setSeed(r[i % 8].nextInt(500) * r[4].nextInt(900));
        password.setCharAt(i, (char) (r[x.nextInt(256) % 8].nextInt(95) + 32));
    }
    return password.toString();
}

---

From source file:net.xxs.util.EncodeUtils.java

/**
 * ????//  w w w. ja va2 s . c om
 * 
 * @param pwd_len
 *            ??
 * @return ?
 */
public static String genRandomNum(int pwd_len) {
    // 35026?+10
    final int maxNum = 10;
    int i; // ??
    int count = 0; // ??
    /*
     * char[] str = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k',
     * 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y',
     * 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' };
     */

    char[] str = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' };

    StringBuffer pwd = new StringBuffer("");
    Random r = new Random();
    r.setSeed(System.currentTimeMillis());
    while (count < pwd_len) {
        // ?????

        i = Math.abs(r.nextInt(maxNum)); // ?36-1

        if (i >= 0 && i < str.length) {
            pwd.append(str[i]);
            count++;
        }
    }

    return pwd.toString();
}

---

From source file:org.apache.hadoop.mapred.gridmix.TestFilePool.java

@BeforeClass
public static void setup() throws IOException {
    final Configuration conf = new Configuration();
    final FileSystem fs = FileSystem.getLocal(conf).getRaw();
    fs.delete(base, true);/*from  w  ww  .  j  ava2s  . c  o m*/
    final Random r = new Random();
    final long seed = r.nextLong();
    r.setSeed(seed);
    LOG.info("seed: " + seed);
    fs.mkdirs(base);
    for (int i = 0; i < NFILES; ++i) {
        Path file = base;
        for (double d = 0.6; d > 0.0; d *= 0.8) {
            if (r.nextDouble() < d) {
                file = new Path(base, Integer.toString(r.nextInt(3)));
                continue;
            }
            break;
        }
        OutputStream out = null;
        try {
            out = fs.create(new Path(file, "" + (char) ('A' + i)));
            final byte[] b = new byte[1024];
            Arrays.fill(b, (byte) ('A' + i));
            for (int len = ((i % 13) + 1) * 1024; len > 0; len -= 1024) {
                out.write(b);
            }
        } finally {
            if (out != null) {
                out.close();
            }
        }
    }
}

---

From source file:org.apache.hadoop.mapred.gridmix.TestGridmixRecord.java

static void eqSeedTest(GridmixRecord x, GridmixRecord y, int max) throws Exception {
    final Random r = new Random();
    final long s = r.nextLong();
    r.setSeed(s);
    LOG.info("eqSeed: " + s);
    assertEquals(x.fixedBytes(), y.fixedBytes());
    final int min = x.fixedBytes() + 1;
    final DataOutputBuffer out1 = new DataOutputBuffer();
    final DataOutputBuffer out2 = new DataOutputBuffer();
    for (int i = min; i < max; ++i) {
        final long seed = r.nextLong();
        setSerialize(x, seed, i, out1);/*from   ww  w .  jav  a2  s  . co  m*/
        setSerialize(y, seed, i, out2);
        assertEquals(x, y);
        assertEquals(x.hashCode(), y.hashCode());

        // verify written contents match
        assertEquals(out1.getLength(), out2.getLength());
        // assumes that writes will grow buffer deterministically
        assertEquals("Bad test", out1.getData().length, out2.getData().length);
        assertArrayEquals(out1.getData(), out2.getData());
    }
}

---

From source file:org.apache.hadoop.mapred.gridmix.TestGridmixRecord.java

static void lengthTest(GridmixRecord x, GridmixRecord y, int min, int max) throws Exception {
    final Random r = new Random();
    final long seed = r.nextLong();
    r.setSeed(seed);
    LOG.info("length: " + seed);
    final DataInputBuffer in = new DataInputBuffer();
    final DataOutputBuffer out1 = new DataOutputBuffer();
    final DataOutputBuffer out2 = new DataOutputBuffer();
    for (int i = min; i < max; ++i) {
        setSerialize(x, r.nextLong(), i, out1);
        // check write
        assertEquals(i, out1.getLength());
        // write to stream
        x.write(out2);//from w w w.j a  va  2  s .c  om
        // check read
        in.reset(out1.getData(), 0, out1.getLength());
        y.readFields(in);
        assertEquals(i, x.getSize());
        assertEquals(i, y.getSize());
    }
    // check stream read
    in.reset(out2.getData(), 0, out2.getLength());
    for (int i = min; i < max; ++i) {
        y.readFields(in);
        assertEquals(i, y.getSize());
    }
}

---

From source file:org.apache.hadoop.mapred.gridmix.TestGridmixRecord.java

static void randomReplayTest(GridmixRecord x, GridmixRecord y, int min, int max) throws Exception {
    final Random r = new Random();
    final long seed = r.nextLong();
    r.setSeed(seed);
    LOG.info("randReplay: " + seed);
    final DataOutputBuffer out1 = new DataOutputBuffer();
    for (int i = min; i < max; ++i) {
        final int s = out1.getLength();
        x.setSeed(r.nextLong());// w  w w  . j a  v a 2s  . c o  m
        x.setSize(i);
        x.write(out1);
        assertEquals(i, out1.getLength() - s);
    }
    final DataInputBuffer in = new DataInputBuffer();
    in.reset(out1.getData(), 0, out1.getLength());
    final DataOutputBuffer out2 = new DataOutputBuffer();
    // deserialize written records, write to separate buffer
    for (int i = min; i < max; ++i) {
        final int s = in.getPosition();
        y.readFields(in);
        assertEquals(i, in.getPosition() - s);
        y.write(out2);
    }
    // verify written contents match
    assertEquals(out1.getLength(), out2.getLength());
    // assumes that writes will grow buffer deterministically
    assertEquals("Bad test", out1.getData().length, out2.getData().length);
    assertArrayEquals(out1.getData(), out2.getData());
}

---

• «
• 1
• 2
• 3
• 4
• 5
• 6
• 7
• 8
• 9
• »