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Diffstat (limited to 'src/Java/gtPlusPlus/api/objects/random')
3 files changed, 0 insertions, 998 deletions
diff --git a/src/Java/gtPlusPlus/api/objects/random/CSPRNG_DO_NOT_USE.java b/src/Java/gtPlusPlus/api/objects/random/CSPRNG_DO_NOT_USE.java deleted file mode 100644 index b2dc984456..0000000000 --- a/src/Java/gtPlusPlus/api/objects/random/CSPRNG_DO_NOT_USE.java +++ /dev/null @@ -1,271 +0,0 @@ -/* - * Copyright 2005, Nick Galbreath -- nickg [at] modp [dot] com - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions are - * met: - * - * Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * - * Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * - * Neither the name of the modp.com nor the names of its - * contributors may be used to endorse or promote products derived from - * this software without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR - * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT - * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, - * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT - * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, - * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY - * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE - * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - * - * This is the standard "new" BSD license: - * http://www.opensource.org/licenses/bsd-license.php - */ - -package gtPlusPlus.api.objects.random; -import java.math.BigInteger; -import java.security.SecureRandom; -import java.util.Random; - -import gtPlusPlus.api.interfaces.IRandomGenerator; -import gtPlusPlus.core.util.Utils; - -/** - * The Blum-Blum-Shub random number generator. - * - * <p> - * The Blum-Blum-Shub is a "cryptographically secure" random number - * generator. It has been proven that predicting the ouput - * is equivalent to factoring <i>n</i>, a large integer generated - * from two prime numbers. - * </p> - * - * <p> - * The Algorithm: - * </p> - * <ol> - * <li> - * (setup) generate two secret prime numbers <i>p</i>, <i>q</i> such that - * <i>p</i> ≠ <i>q</i>, <i>p</i> ≡ 3 mod 4, <i>q</i> ≡ 3 mod 4. - * </li> - * <li> (setup) compute <i>n</i> = <i>pq</i>. <i>n</i> can be re-used, but - * <i>p</i>, and <i>q</i> are secret and should be disposed of.</li> - * <li> Generate a (secure) random seed <i>s</i> in the range [1, <i>n</i> -1] - * such that gcd(<i>s</i>, <i>n</i>) = 1. - * <li> Compute <i>x</i> = <i>s</i><sup>2</sup> mod <i>n</i></li> - * <li> Compute a single random bit with: - * <ol> - * <li> <i>x</i> = <i>x</i><sup>2</sup> mod <i>n</i></li> - * <li> return Least-Significant-Bit(<i>x</i>) (i.e. <i>x</i> & 1)</li> - * </ol> - * Repeat as necessary. - * </li> - * </ol> - * - * <p> - * The code originally appeared in <a href="http://modp.com/cida/"><i>Cryptography for - * Internet and Database Applications </i>, Chapter 4, pages 174-177</a> - * </p> - * <p> - * More details are in the <a href="http://www.cacr.math.uwaterloo.ca/hac/"><i>Handbook of Applied Cryptography</i></a>, - * <a href="http://www.cacr.math.uwaterloo.ca/hac/about/chap5.pdf">Section 5.5.2</a> - * </p> - * - * @author Nick Galbreath -- nickg [at] modp [dot] com - * @version 3 -- 06-Jul-2005 - * - */ -public class CSPRNG_DO_NOT_USE extends Random implements IRandomGenerator { - - // pre-compute a few values - private static final BigInteger two = BigInteger.valueOf(2L); - - private static final BigInteger three = BigInteger.valueOf(3L); - - private static final BigInteger four = BigInteger.valueOf(4L); - - /** - * main parameter - */ - private BigInteger n; - - private BigInteger state; - - /** - * Generate appropriate prime number for use in Blum-Blum-Shub. - * - * This generates the appropriate primes (p = 3 mod 4) needed to compute the - * "n-value" for Blum-Blum-Shub. - * - * @param bits Number of bits in prime - * @param rand A source of randomness - */ - private static BigInteger getPrime(int bits, Random rand) { - BigInteger p; - while (true) { - p = new BigInteger(bits, 100, rand); - if (p.mod(four).equals(three)) - break; - } - return p; - } - - /** - * This generates the "n value" -- the multiplication of two equally sized - * random prime numbers -- for use in the Blum-Blum-Shub algorithm. - * - * @param bits - * The number of bits of security - * @param rand - * A random instance to aid in generating primes - * @return A BigInteger, the <i>n</i>. - */ - public static BigInteger generateN(int bits, Random rand) { - BigInteger p = getPrime(bits/2, rand); - BigInteger q = getPrime(bits/2, rand); - - // make sure p != q (almost always true, but just in case, check) - while (p.equals(q)) { - q = getPrime(bits, rand); - } - return p.multiply(q); - } - - /** - * Constructor, specifing bits for <i>n</i> - * - * @param bits number of bits - */ - public CSPRNG_DO_NOT_USE(int bits) { - this(bits, new Random()); - } - - /** - * Constructor, generates prime and seed - * - * @param bits - * @param rand - */ - public CSPRNG_DO_NOT_USE(int bits, Random rand) { - this(generateN(bits, rand)); - } - - /** - * A constructor to specify the "n-value" to the Blum-Blum-Shub algorithm. - * The inital seed is computed using Java's internal "true" random number - * generator. - * - * @param n - * The n-value. - */ - public CSPRNG_DO_NOT_USE(BigInteger n) { - this(n, SecureRandom.getSeed(n.bitLength() / 8)); - } - - /** - * A constructor to specify both the n-value and the seed to the - * Blum-Blum-Shub algorithm. - * - * @param n - * The n-value using a BigInteger - * @param seed - * The seed value using a byte[] array. - */ - public CSPRNG_DO_NOT_USE(BigInteger n, byte[] seed) { - this.n = n; - setSeed(seed); - } - - /** - * Sets or resets the seed value and internal state - * - * @param seedBytes - * The new seed. - */ - public void setSeed(byte[] seedBytes) { - // ADD: use hardwired default for n - BigInteger seed = new BigInteger(1, seedBytes); - state = seed.mod(n); - } - - /** - * Returns up to numBit random bits - * - * @return int - */ - @Override - public int next(int numBits) { - // TODO: find out how many LSB one can extract per cycle. - // it is more than one. - int result = 0; - for (int i = numBits; i != 0; --i) { - state = state.modPow(two, n); - result = (result << 1) | (state.testBit(0) == true ? 1 : 0); - } - return result; - } - - - public static CSPRNG_DO_NOT_USE generate(){ - return generate(512); - } - - /** - * @return CSPRNG_DO_NOT_USE - * @Author Draknyte1/Alkalus - */ - public static CSPRNG_DO_NOT_USE generate(int bitsize){ - // First use the internal, stock "true" random number - // generator to get a "true random seed" - SecureRandom r = Utils.generateSecureRandom(); - r.nextInt(); // need to do something for SR to be triggered. - // Use this seed to generate a n-value for Blum-Blum-Shub - // This value can be re-used if desired. - BigInteger nval = CSPRNG_DO_NOT_USE.generateN(bitsize, r); - // now get a seed - byte[] seed = new byte[bitsize/8]; - r.nextBytes(seed); - // now create an instance of BlumBlumShub - CSPRNG_DO_NOT_USE bbs = new CSPRNG_DO_NOT_USE(nval, seed); - return bbs; - } - - - /** - * @return CSPRNG_DO_NOT_USE - * @Author Draknyte1/Alkalus - */ - public static CSPRNG_DO_NOT_USE generate(Random aRandom){ - return generate(512, aRandom); - } - - /** - * @return CSPRNG_DO_NOT_USE - * @Author Draknyte1/Alkalus - */ - public static CSPRNG_DO_NOT_USE generate(int aBitSize, Random aRandom){ - // First use the internal, stock "true" random number - // generator to get a "true random seed" - SecureRandom r = Utils.generateSecureRandom(); - r.nextInt(); // need to do something for SR to be triggered. - // Use this seed to generate a n-value for Blum-Blum-Shub - // This value can be re-used if desired. - int bitsize = aBitSize; - // now create an instance of BlumBlumShub - // do everything almost automatically - CSPRNG_DO_NOT_USE bbs = new CSPRNG_DO_NOT_USE(bitsize, aRandom); - return bbs; - } - -} diff --git a/src/Java/gtPlusPlus/api/objects/random/UUIDGenerator.java b/src/Java/gtPlusPlus/api/objects/random/UUIDGenerator.java deleted file mode 100644 index fec92368f8..0000000000 --- a/src/Java/gtPlusPlus/api/objects/random/UUIDGenerator.java +++ /dev/null @@ -1,449 +0,0 @@ -package gtPlusPlus.api.objects.random; - -import java.io.IOException; -import java.net.InetAddress; -import java.util.Random; -import java.util.UUID; - -/** - * - * Implement modified version of Apache's OpenJPA UUID generator. - * This UUID generator is paired with a Blum-Blum-Shub random number generator - * which in itself is seeded by custom SecureRandom. - * - * The UUID generator class has been converted from a static factory to an instanced factory. - * - */ - -//========================================= APACHE BLOCK ========================================= - -/* - * Licensed to the Apache Software Foundation (ASF) under one - * or more contributor license agreements. See the NOTICE file - * distributed with this work for additional information - * regarding copyright ownership. The ASF licenses this file - * to you under the Apache License, Version 2.0 (the - * "License"); you may not use this file except in compliance - * with the License. You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, - * software distributed under the License is distributed on an - * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY - * KIND, either express or implied. See the License for the - * specific language governing permissions and limitations - * under the License. - */ - -/** - * UUID value generator. Type 1 generator is based on the time-based generator - * in the Apache Commons Id project: http://jakarta.apache.org/commons/sandbox - * /id/uuid.html The type 4 generator uses the standard Java UUID generator. - * - * The type 1 code has been vastly simplified and modified to replace the - * ethernet address of the host machine with the IP, since we do not want to - * require native libs and Java cannot access the MAC address directly. - * - * In spirit, implements the IETF UUID draft specification, found here:<br /> - * http://www1.ics.uci.edu/~ejw/authoring/uuid-guid/draft-leach-uuids-guids-01 - * .txt - * - * @author Abe White, Kevin Sutter - * @since 0.3.3 - */ -public class UUIDGenerator { - - // supported UUID types - public static final int TYPE1 = 1; - public static final int TYPE4 = 4; - // indexes within the uuid array for certain boundaries - private static final byte IDX_TIME_HI = 6; - private static final byte IDX_TYPE = 6; // multiplexed - private static final byte IDX_TIME_MID = 4; - private static final byte IDX_TIME_LO = 0; - private static final byte IDX_TIME_SEQ = 8; - private static final byte IDX_VARIATION = 8; // multiplexed - // indexes and lengths within the timestamp for certain boundaries - private static final byte TS_TIME_LO_IDX = 4; - private static final byte TS_TIME_LO_LEN = 4; - private static final byte TS_TIME_MID_IDX = 2; - private static final byte TS_TIME_MID_LEN = 2; - private static final byte TS_TIME_HI_IDX = 0; - private static final byte TS_TIME_HI_LEN = 2; - // offset to move from 1/1/1970, which is 0-time for Java, to gregorian - // 0-time 10/15/1582, and multiplier to go from 100nsec to msec units - private static final long GREG_OFFSET = 0xB1D069B5400L; - private static final long MILLI_MULT = 10000L; - // type of UUID -- time based - private final static byte TYPE_TIME_BASED = 0x10; - // random number generator used to reduce conflicts with other JVMs, and - // hasher for strings. - private Random RANDOM; - // 4-byte IP address + 2 random bytes to compensate for the fact that - // the MAC address is usually 6 bytes - private byte[] IP; - // counter is initialized to 0 and is incremented for each uuid request - // within the same timestamp window. - private int _counter; - // current timestamp (used to detect multiple uuid requests within same - // timestamp) - private long _currentMillis; - // last used millis time, and a semi-random sequence that gets reset - // when it overflows - private long _lastMillis = 0L; - private static final int MAX_14BIT = 0x3FFF; - private short _seq = 0; - private boolean type1Initialized = false; /* - * Initializer for type 1 UUIDs. Creates random generator and genenerates - * the node portion of the UUID using the IP address. - */ - private synchronized void initializeForType1() { - if (type1Initialized == true) { - return; - } - // note that secure random is very slow the first time - // it is used; consider switching to a standard random - RANDOM = CSPRNG_DO_NOT_USE.generate(); - _seq = (short) RANDOM.nextInt(MAX_14BIT); - - byte[] ip = null; - try { - ip = InetAddress.getLocalHost().getAddress(); - } catch (IOException ioe) { - throw new RuntimeException(ioe); - } - IP = new byte[6]; - RANDOM.nextBytes(IP); - //OPENJPA-2055: account for the fact that 'getAddress' - //may return an IPv6 address which is 16 bytes wide. - for( int i = 0 ; i < ip.length; ++i ) { - IP[2+(i%4)] ^= ip[i]; - } - type1Initialized = true; - } - /** - * Return a unique UUID value. - */ - public byte[] next(int type) { - if (type == TYPE4) { - return createType4(); - } - return createType1(); - } - /* - * Creates a type 1 UUID - */ - public byte[] createType1() { - if (type1Initialized == false) { - initializeForType1(); - } - // set ip addr - byte[] uuid = new byte[16]; - System.arraycopy(IP, 0, uuid, 10, IP.length); - // Set time info. Have to do this processing within a synchronized - // block because of the statics... - long now = 0; - synchronized (UUIDGenerator.class) { - // Get the time to use for this uuid. This method has the side - // effect of modifying the clock sequence, as well. - now = getTime(); - // Insert the resulting clock sequence into the uuid - uuid[IDX_TIME_SEQ] = (byte) ((_seq & 0x3F00) >>> 8); - uuid[IDX_VARIATION] |= 0x80; - uuid[IDX_TIME_SEQ+1] = (byte) (_seq & 0xFF); - } - // have to break up time because bytes are spread through uuid - byte[] timeBytes = Bytes.toBytes(now); - // Copy time low - System.arraycopy(timeBytes, TS_TIME_LO_IDX, uuid, IDX_TIME_LO, - TS_TIME_LO_LEN); - // Copy time mid - System.arraycopy(timeBytes, TS_TIME_MID_IDX, uuid, IDX_TIME_MID, - TS_TIME_MID_LEN); - // Copy time hi - System.arraycopy(timeBytes, TS_TIME_HI_IDX, uuid, IDX_TIME_HI, - TS_TIME_HI_LEN); - //Set version (time-based) - uuid[IDX_TYPE] |= TYPE_TIME_BASED; // 0001 0000 - return uuid; - } - /* - * Creates a type 4 UUID - */ - private byte[] createType4() { - UUID type4 = UUID.randomUUID(); - byte[] uuid = new byte[16]; - longToBytes(type4.getMostSignificantBits(), uuid, 0); - longToBytes(type4.getLeastSignificantBits(), uuid, 8); - return uuid; - } - /* - * Converts a long to byte values, setting them in a byte array - * at a given starting position. - */ - private void longToBytes(long longVal, byte[] buf, int sPos) { - sPos += 7; - for(int i = 0; i < 8; i++) - buf[sPos-i] = (byte)(longVal >>> (i * 8)); - } - - /** - * Return the next unique uuid value as a 16-character string. - */ - public String nextString(int type) { - byte[] bytes = next(type); - try { - return new String(bytes, "ISO-8859-1"); - } catch (Exception e) { - return new String(bytes); - } - } - /** - * Return the next unique uuid value as a 32-character hex string. - */ - public String nextHex(int type) { - return Base16Encoder.encode(next(type)); - } - /** - * Get the timestamp to be used for this uuid. Must be called from - * a synchronized block. - * - * @return long timestamp - */ - // package-visibility for testing - private long getTime() { - if (RANDOM == null) - initializeForType1(); - long newTime = getUUIDTime(); - if (newTime <= _lastMillis) { - incrementSequence(); - newTime = getUUIDTime(); - } - _lastMillis = newTime; - return newTime; - } - /** - * Gets the appropriately modified timestamep for the UUID. Must be called - * from a synchronized block. - * - * @return long timestamp in 100ns intervals since the Gregorian change - * offset - */ - private long getUUIDTime() { - if (_currentMillis != System.currentTimeMillis()) { - _currentMillis = System.currentTimeMillis(); - _counter = 0; // reset counter - } - // check to see if we have created too many uuid's for this timestamp - if (_counter + 1 >= MILLI_MULT) { - // Original algorithm threw exception. Seemed like overkill. - // Let's just increment the timestamp instead and start over... - _currentMillis++; - _counter = 0; - } - // calculate time as current millis plus offset times 100 ns ticks - long currentTime = (_currentMillis + GREG_OFFSET) * MILLI_MULT; - // return the uuid time plus the artificial tick counter incremented - return currentTime + _counter++; - } - /** - * Increments the clock sequence for this uuid. Must be called from a - * synchronized block. - */ - private void incrementSequence() { - // increment, but if it's greater than its 14-bits, reset it - if (++_seq > MAX_14BIT) { - _seq = (short) RANDOM.nextInt(MAX_14BIT); // semi-random - } - } - - //Add Dependant classes internally - - /** - * This class came from the Apache Commons Id sandbox project in support - * of the UUIDGenerator implementation. - * - * <p>Static methods for managing byte arrays (all methods follow Big - * Endian order where most significant bits are in front).</p> - */ - public static final class Bytes { - /** - * <p>Hide constructor in utility class.</p> - */ - private Bytes() { - } - /** - * Appends two bytes array into one. - * - * @param a A byte[]. - * @param b A byte[]. - * @return A byte[]. - */ - public static byte[] append(byte[] a, byte[] b) { - byte[] z = new byte[a.length + b.length]; - System.arraycopy(a, 0, z, 0, a.length); - System.arraycopy(b, 0, z, a.length, b.length); - return z; - } - /** - * Returns a 8-byte array built from a long. - * - * @param n The number to convert. - * @return A byte[]. - */ - public static byte[] toBytes(long n) { - return toBytes(n, new byte[8]); - } - /** - * Build a 8-byte array from a long. No check is performed on the - * array length. - * - * @param n The number to convert. - * @param b The array to fill. - * @return A byte[]. - */ - public static byte[] toBytes(long n, byte[] b) { - b[7] = (byte) (n); - n >>>= 8; - b[6] = (byte) (n); - n >>>= 8; - b[5] = (byte) (n); - n >>>= 8; - b[4] = (byte) (n); - n >>>= 8; - b[3] = (byte) (n); - n >>>= 8; - b[2] = (byte) (n); - n >>>= 8; - b[1] = (byte) (n); - n >>>= 8; - b[0] = (byte) (n); - - return b; - } - /** - * Build a long from first 8 bytes of the array. - * - * @param b The byte[] to convert. - * @return A long. - */ - public static long toLong(byte[] b) { - return ((((long) b[7]) & 0xFF) - + ((((long) b[6]) & 0xFF) << 8) - + ((((long) b[5]) & 0xFF) << 16) - + ((((long) b[4]) & 0xFF) << 24) - + ((((long) b[3]) & 0xFF) << 32) - + ((((long) b[2]) & 0xFF) << 40) - + ((((long) b[1]) & 0xFF) << 48) - + ((((long) b[0]) & 0xFF) << 56)); - } - /** - * Compares two byte arrays for equality. - * - * @param a A byte[]. - * @param b A byte[]. - * @return True if the arrays have identical contents. - */ - public static boolean areEqual(byte[] a, byte[] b) { - int aLength = a.length; - if (aLength != b.length) { - return false; - } - for (int i = 0; i < aLength; i++) { - if (a[i] != b[i]) { - return false; - } - } - return true; - } - /** - * <p>Compares two byte arrays as specified by <code>Comparable</code>. - * - * @param lhs - left hand value in the comparison operation. - * @param rhs - right hand value in the comparison operation. - * @return a negative integer, zero, or a positive integer as - * <code>lhs</code> is less than, equal to, or greater than - * <code>rhs</code>. - */ - public static int compareTo(byte[] lhs, byte[] rhs) { - if (lhs == rhs) { - return 0; - } - if (lhs == null) { - return -1; - } - if (rhs == null) { - return +1; - } - if (lhs.length != rhs.length) { - return ((lhs.length < rhs.length) ? -1 : +1); - } - for (int i = 0; i < lhs.length; i++) { - if (lhs[i] < rhs[i]) { - return -1; - } else if (lhs[i] > rhs[i]) { - return 1; - } - } - return 0; - } - /** - * Build a short from first 2 bytes of the array. - * - * @param b The byte[] to convert. - * @return A short. - */ - public static short toShort(byte[] b) { - return (short) ((b[1] & 0xFF) + ((b[0] & 0xFF) << 8)); - } - } - /** - * Base 16 encoder. - * - * @author Marc Prud'hommeaux - */ - public static final class Base16Encoder { - - private final static char[] HEX = new char[]{ - '0', '1', '2', '3', '4', '5', '6', '7', - '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' }; - /** - * Convert bytes to a base16 string. - */ - public static String encode(byte[] byteArray) { - StringBuilder hexBuffer = new StringBuilder(byteArray.length * 2); - for (int i = 0; i < byteArray.length; i++) - for (int j = 1; j >= 0; j--) - hexBuffer.append(HEX[(byteArray[i] >> (j * 4)) & 0xF]); - return hexBuffer.toString(); - } - /** - * Convert a base16 string into a byte array. - */ - public static byte[] decode(String s) { - int len = s.length(); - byte[] r = new byte[len / 2]; - for (int i = 0; i < r.length; i++) { - int digit1 = s.charAt(i * 2), digit2 = s.charAt(i * 2 + 1); - if (digit1 >= '0' && digit1 <= '9') - digit1 -= '0'; - else if (digit1 >= 'A' && digit1 <= 'F') - digit1 -= 'A' - 10; - if (digit2 >= '0' && digit2 <= '9') - digit2 -= '0'; - else if (digit2 >= 'A' && digit2 <= 'F') - digit2 -= 'A' - 10; - - r[i] = (byte) ((digit1 << 4) + digit2); - } - return r; - } - } - - - -} - -//========================================= APACHE BLOCK ========================================= - diff --git a/src/Java/gtPlusPlus/api/objects/random/XSTR.java b/src/Java/gtPlusPlus/api/objects/random/XSTR.java deleted file mode 100644 index 6ce1cbeb6c..0000000000 --- a/src/Java/gtPlusPlus/api/objects/random/XSTR.java +++ /dev/null @@ -1,278 +0,0 @@ -package gtPlusPlus.api.objects.random; -/** - * A subclass of java.util.random that implements the Xorshift random number - * generator - * - * - it is 30% faster than the generator from Java's library - it produces - * random sequences of higher quality than java.util.Random - this class also - * provides a clone() function - * - * Usage: XSRandom rand = new XSRandom(); //Instantiation x = rand.nextInt(); - * //pull a random number - * - * To use the class in legacy code, you may also instantiate an XSRandom object - * and assign it to a java.util.Random object: java.util.Random rand = new - * XSRandom(); - * - * for an explanation of the algorithm, see - * http://demesos.blogspot.com/2011/09/pseudo-random-number-generators.html - * - * @author Wilfried Elmenreich University of Klagenfurt/Lakeside Labs - * http://www.elmenreich.tk - * - * This code is released under the GNU Lesser General Public License Version 3 - * http://www.gnu.org/licenses/lgpl-3.0.txt - */ - -import java.util.Random; -import java.util.concurrent.atomic.AtomicLong; - -/** - * XSTR - Xorshift ThermiteRandom - * Modified by Bogdan-G - * 03.06.2016 - * version 0.0.4 - */ -public class XSTR extends Random implements Cloneable { - - private static final long serialVersionUID = 6208727693524452904L; - private long seed; - private long last; - private static final long GAMMA = 0x9e3779b97f4a7c15L; - private static final int PROBE_INCREMENT = 0x9e3779b9; - private static final long SEEDER_INCREMENT = 0xbb67ae8584caa73bL; - private static final double DOUBLE_UNIT = 0x1.0p-53; // 1.0 / (1L << 53) - private static final float FLOAT_UNIT = 0x1.0p-24f; // 1.0f / (1 << 24) - - /* - MODIFIED BY: Robotia - Modification: Implemented Random class seed generator - */ - /** - * Creates a new pseudo random number generator. The seed is initialized to - * the current time, as if by - * <code>setSeed(System.currentTimeMillis());</code>. - */ - public XSTR() { - this(seedUniquifier() ^ System.nanoTime()); - } - private static final AtomicLong seedUniquifier - = new AtomicLong(8682522807148012L); - - private static long seedUniquifier() { - // L'Ecuyer, "Tables of Linear Congruential Generators of - // Different Sizes and Good Lattice Structure", 1999 - for (;;) { - final long current = seedUniquifier.get(); - final long next = current * 181783497276652981L; - if (seedUniquifier.compareAndSet(current, next)) { - return next; - } - } - } - - /** - * Creates a new pseudo random number generator, starting with the specified - * seed, using <code>setSeed(seed);</code>. - * - * @param seed the initial seed - */ - public XSTR(final long seed) { - this.seed = seed; - } - @Override - public boolean nextBoolean() { - return this.next(1) != 0; - } - - @Override - public double nextDouble() { - return (((long)(this.next(26)) << 27) + this.next(27)) * DOUBLE_UNIT; - } - /** - * Returns the current state of the seed, can be used to clone the object - * - * @return the current seed - */ - public synchronized long getSeed() { - return this.seed; - } - - /** - * Sets the seed for this pseudo random number generator. As described - * above, two instances of the same random class, starting with the same - * seed, produce the same results, if the same methods are called. - * - * @param seed the new seed - */ - @Override - public synchronized void setSeed(final long seed) { - this.seed = seed; - } - - /** - * @return Returns an XSRandom object with the same state as the original - */ - @Override - public XSTR clone() { - try { - super.clone(); - } - catch (CloneNotSupportedException e) { - // TODO Auto-generated catch block - e.printStackTrace(); - } - return new XSTR(this.getSeed()); - } - - /** - * Implementation of George Marsaglia's elegant Xorshift random generator - * 30% faster and better quality than the built-in java.util.random see also - * see http://www.javamex.com/tutorials/random_numbers/xorshift.shtml - * - * @param nbits - * @return - */ - @Override - public int next(final int nbits) { - long x = this.seed; - x ^= (x << 21); - x ^= (x >>> 35); - x ^= (x << 4); - this.seed = x; - x &= ((1L << nbits) - 1); - return (int) x; - } - boolean haveNextNextGaussian = false; - double nextNextGaussian = 0; - @Override - synchronized public double nextGaussian() { - // See Knuth, ACP, Section 3.4.1 Algorithm C. - if (this.haveNextNextGaussian) { - this.haveNextNextGaussian = false; - return this.nextNextGaussian; - } - double v1, v2, s; - do { - v1 = (2 * this.nextDouble()) - 1; // between -1 and 1 - v2 = (2 * this.nextDouble()) - 1; // between -1 and 1 - s = (v1 * v1) + (v2 * v2); - } while ((s >= 1) || (s == 0)); - final double multiplier = StrictMath.sqrt((-2 * StrictMath.log(s))/s); - this.nextNextGaussian = v2 * multiplier; - this.haveNextNextGaussian = true; - return v1 * multiplier; - } - /** - * Returns a pseudorandom, uniformly distributed {@code int} value between 0 - * (inclusive) and the specified value (exclusive), drawn from this random - * number generator's sequence. The general contract of {@code nextInt} is - * that one {@code int} value in the specified range is pseudorandomly - * generated and returned. All {@code bound} possible {@code int} values are - * produced with (approximately) equal probability. The method - * {@code nextInt(int bound)} is implemented by class {@code Random} as if - * by: - * <pre> {@code - * public int nextInt(int bound) { - * if (bound <= 0) - * throw new IllegalArgumentException("bound must be positive"); - * - * if ((bound & -bound) == bound) // i.e., bound is a power of 2 - * return (int)((bound * (long)next(31)) >> 31); - * - * int bits, val; - * do { - * bits = next(31); - * val = bits % bound; - * } while (bits - val + (bound-1) < 0); - * return val; - * }}</pre> - * - * <p>The hedge "approx - * imately" is used in the foregoing description only because the next - * method is only approximately an unbiased source of independently chosen - * bits. If it were a perfect source of randomly chosen bits, then the - * algorithm shown would choose {@code int} values from the stated range - * with perfect uniformity. - * <p> - * The algorithm is slightly tricky. It rejects values that would result in - * an uneven distribution (due to the fact that 2^31 is not divisible by n). - * The probability of a value being rejected depends on n. The worst case is - * n=2^30+1, for which the probability of a reject is 1/2, and the expected - * number of iterations before the loop terminates is 2. - * <p> - * The algorithm treats the case where n is a power of two specially: it - * returns the correct number of high-order bits from the underlying - * pseudo-random number generator. In the absence of special treatment, the - * correct number of <i>low-order</i> bits would be returned. Linear - * congruential pseudo-random number generators such as the one implemented - * by this class are known to have short periods in the sequence of values - * of their low-order bits. Thus, this special case greatly increases the - * length of the sequence of values returned by successive calls to this - * method if n is a small power of two. - * - * @param bound the upper bound (exclusive). Must be positive. - * @return the next pseudorandom, uniformly distributed {@code int} value - * between zero (inclusive) and {@code bound} (exclusive) from this random - * number generator's sequence - * @throws IllegalArgumentException if bound is not positive - * @since 1.2 - */ - @Override - public int nextInt(final int bound) { - final int newBound; - if (bound <= 0) { - newBound = 1; - //throw new RuntimeException("BadBound"); - } - else { - newBound = bound; - } - - /*int r = next(31); - int m = bound - 1; - if ((bound & m) == 0) // i.e., bound is a power of 2 - { - r = (int) ((bound * (long) r) >> 31); - } else { - for (int u = r; - u - (r = u % bound) + m < 0; - u = next(31)) - ; - } - return r;*/ - //speedup, new nextInt ~+40% - this.last = this.seed ^ (this.seed << 21); - this.last ^= (this.last >>> 35); - this.last ^= (this.last << 4); - this.seed = this.last; - final int out = (int) this.last % newBound; - return (out < 0) ? -out : out; - } - @Override - public int nextInt() { - return this.next(32); - } - - @Override - public float nextFloat() { - return this.next(24) * FLOAT_UNIT; - } - - @Override - public long nextLong() { - // it's okay that the bottom word remains signed. - return ((long)(this.next(32)) << 32) + this.next(32); - } - - @Override - public void nextBytes(final byte[] bytes_arr) { - for (int iba = 0, lenba = bytes_arr.length; iba < lenba; ) { - for (int rndba = this.nextInt(), - nba = Math.min(lenba - iba, Integer.SIZE/Byte.SIZE); - nba-- > 0; rndba >>= Byte.SIZE) { - bytes_arr[iba++] = (byte)rndba; - } - } - } -}
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