Merge Argeo Util and parts of Argeo JCR in Argeo Core.
[lgpl/argeo-commons.git] / org.argeo.core / src / org / argeo / util / UuidUtils.java
diff --git a/org.argeo.core/src/org/argeo/util/UuidUtils.java b/org.argeo.core/src/org/argeo/util/UuidUtils.java
new file mode 100644 (file)
index 0000000..ebe0978
--- /dev/null
@@ -0,0 +1,374 @@
+package org.argeo.util;
+
+import java.net.InetAddress;
+import java.net.NetworkInterface;
+import java.net.SocketException;
+import java.net.UnknownHostException;
+import java.security.SecureRandom;
+import java.time.Duration;
+import java.time.LocalDateTime;
+import java.time.ZoneOffset;
+import java.util.BitSet;
+import java.util.Random;
+import java.util.UUID;
+import java.util.concurrent.atomic.AtomicInteger;
+
+/**
+ * Utilities to simplify and extends usage of {@link UUID}. Only the RFC 4122
+ * variant (also known as Leach–Salz variant) is supported.
+ */
+public class UuidUtils {
+       /** Nil UUID (00000000-0000-0000-0000-000000000000). */
+       public final static UUID NIL_UUID = UUID.fromString("00000000-0000-0000-0000-000000000000");
+       public final static LocalDateTime GREGORIAN_START = LocalDateTime.of(1582, 10, 15, 0, 0, 0);
+
+       private final static long MOST_SIG_VERSION1 = (1l << 12);
+       private final static long LEAST_SIG_RFC4122_VARIANT = (1l << 63);
+
+       private final static SecureRandom RANDOM;
+       private final static AtomicInteger CLOCK_SEQUENCE;
+       private final static byte[] HARDWARE_ADDRESS;
+       /** A start timestamp to which {@link System#nanoTime()}/100 can be added. */
+       private final static long START_TIMESTAMP;
+       static {
+               RANDOM = new SecureRandom();
+               CLOCK_SEQUENCE = new AtomicInteger(RANDOM.nextInt(16384));
+               HARDWARE_ADDRESS = getHardwareAddress();
+
+               long nowVm = System.nanoTime() / 100;
+               Duration duration = Duration.between(GREGORIAN_START, LocalDateTime.now(ZoneOffset.UTC));
+               START_TIMESTAMP = (duration.getSeconds() * 10000000 + duration.getNano() / 100) - nowVm;
+       }
+
+       private static byte[] getHardwareAddress() {
+               InetAddress localHost;
+               try {
+                       localHost = InetAddress.getLocalHost();
+                       try {
+                               NetworkInterface nic = NetworkInterface.getByInetAddress(localHost);
+                               return nic.getHardwareAddress();
+                       } catch (SocketException e) {
+                               return null;
+                       }
+               } catch (UnknownHostException e) {
+                       return null;
+               }
+
+       }
+
+       public static UUID timeUUIDwithRandomNode() {
+               long timestamp = START_TIMESTAMP + System.nanoTime() / 100;
+               return timeUUID(timestamp, RANDOM);
+       }
+
+       public static UUID timeUUID(long timestamp, Random random) {
+               byte[] node = new byte[6];
+               random.nextBytes(node);
+               node[0] = (byte) (node[0] | 1);
+               long clockSequence = CLOCK_SEQUENCE.incrementAndGet();
+               return timeUUID(timestamp, clockSequence, node);
+       }
+
+       public static UUID timeUUID() {
+               long timestamp = START_TIMESTAMP + System.nanoTime() / 100;
+               return timeUUID(timestamp);
+       }
+
+       public static UUID timeUUID(long timestamp) {
+               if (HARDWARE_ADDRESS == null)
+                       return timeUUID(timestamp, RANDOM);
+               long clockSequence = CLOCK_SEQUENCE.incrementAndGet();
+               return timeUUID(timestamp, clockSequence, HARDWARE_ADDRESS);
+       }
+
+       public static UUID timeUUID(long timestamp, NetworkInterface nic) {
+               byte[] node;
+               try {
+                       node = nic.getHardwareAddress();
+               } catch (SocketException e) {
+                       throw new IllegalStateException("Cannot get hardware address", e);
+               }
+               long clockSequence = CLOCK_SEQUENCE.incrementAndGet();
+               return timeUUID(timestamp, clockSequence, node);
+       }
+
+       public static UUID timeUUID(LocalDateTime time, long clockSequence, byte[] node) {
+               Duration duration = Duration.between(GREGORIAN_START, time);
+               // Number of 100 ns intervals in one second: 1000000000 / 100 = 10000000
+               long timestamp = duration.getSeconds() * 10000000 + duration.getNano() / 100;
+               return timeUUID(timestamp, clockSequence, node);
+       }
+
+       public static UUID timeUUID(long timestamp, long clockSequence, byte[] node) {
+               assert node.length >= 6;
+
+               long mostSig = MOST_SIG_VERSION1 // base for version 1 UUID
+                               | ((timestamp & 0xFFFFFFFFL) << 32) // time_low
+                               | (((timestamp >> 32) & 0xFFFFL) << 16) // time_mid
+                               | ((timestamp >> 48) & 0x0FFFL);// time_hi_and_version
+
+               long leastSig = LEAST_SIG_RFC4122_VARIANT // base for Leach–Salz UUID
+                               | (((clockSequence & 0x3F00) >> 8) << 56) // clk_seq_hi_res
+                               | ((clockSequence & 0xFF) << 48) // clk_seq_low
+                               | (node[0] & 0xFFL) //
+                               | ((node[1] & 0xFFL) << 8) //
+                               | ((node[2] & 0xFFL) << 16) //
+                               | ((node[3] & 0xFFL) << 24) //
+                               | ((node[4] & 0xFFL) << 32) //
+                               | ((node[5] & 0xFFL) << 40); //
+//             for (int i = 0; i < 6; i++) {
+//                     leastSig = leastSig | ((node[i] & 0xFFL) << (8 * i));
+//             }
+               UUID uuid = new UUID(mostSig, leastSig);
+
+               // tests
+               assert uuid.node() == BitSet.valueOf(node).toLongArray()[0];
+               assert uuid.timestamp() == timestamp;
+               assert uuid.clockSequence() == clockSequence;
+               assert uuid.version() == 1;
+               assert uuid.variant() == 2;
+               return uuid;
+       }
+
+       @Deprecated
+       public static UUID timeBasedUUID() {
+               return timeBasedUUID(LocalDateTime.now(ZoneOffset.UTC));
+       }
+
+       @Deprecated
+       public static UUID timeBasedRandomUUID() {
+               return timeBasedRandomUUID(LocalDateTime.now(ZoneOffset.UTC), RANDOM);
+       }
+
+       @Deprecated
+       public static UUID timeBasedUUID(LocalDateTime time) {
+               if (HARDWARE_ADDRESS == null)
+                       return timeBasedRandomUUID(time, RANDOM);
+               return timeBasedUUID(time, BitSet.valueOf(HARDWARE_ADDRESS));
+       }
+
+       @Deprecated
+       public static UUID timeBasedAddressUUID(LocalDateTime time, NetworkInterface nic) throws SocketException {
+               byte[] nodeBytes = nic.getHardwareAddress();
+               BitSet node = BitSet.valueOf(nodeBytes);
+               return timeBasedUUID(time, node);
+       }
+
+       @Deprecated
+       public static UUID timeBasedRandomUUID(LocalDateTime time, Random random) {
+               byte[] nodeBytes = new byte[6];
+               random.nextBytes(nodeBytes);
+               BitSet node = BitSet.valueOf(nodeBytes);
+               // set random marker
+               node.set(0, true);
+               return timeBasedUUID(time, node);
+       }
+
+       @Deprecated
+       public static UUID timeBasedUUID(LocalDateTime time, BitSet node) {
+               // most significant
+               Duration duration = Duration.between(GREGORIAN_START, time);
+
+               // Number of 100 ns intervals in one second: 1000000000 / 100 = 10000000
+               long timeNanos = duration.getSeconds() * 10000000 + duration.getNano() / 100;
+               BitSet timeBits = BitSet.valueOf(new long[] { timeNanos });
+               assert timeBits.length() <= 60;
+
+               int clockSequence;
+               synchronized (CLOCK_SEQUENCE) {
+                       clockSequence = CLOCK_SEQUENCE.incrementAndGet();
+                       if (clockSequence > 16384)
+                               CLOCK_SEQUENCE.set(0);
+               }
+               BitSet clockSequenceBits = BitSet.valueOf(new long[] { clockSequence });
+
+               // Build the UUID, bit by bit
+               // see https://tools.ietf.org/html/rfc4122#section-4.2.2
+               // time
+               BitSet time_low = new BitSet(32);
+               BitSet time_mid = new BitSet(16);
+               BitSet time_hi_and_version = new BitSet(16);
+
+               for (int i = 0; i < 60; i++) {
+                       if (i < 32)
+                               time_low.set(i, timeBits.get(i));
+                       else if (i < 48)
+                               time_mid.set(i - 32, timeBits.get(i));
+                       else
+                               time_hi_and_version.set(i - 48, timeBits.get(i));
+               }
+               // version
+               time_hi_and_version.set(12, true);
+               time_hi_and_version.set(13, false);
+               time_hi_and_version.set(14, false);
+               time_hi_and_version.set(15, false);
+
+               // clock sequence
+               BitSet clk_seq_hi_res = new BitSet(8);
+               BitSet clk_seq_low = new BitSet(8);
+               for (int i = 0; i < 8; i++) {
+                       clk_seq_low.set(i, clockSequenceBits.get(i));
+               }
+               for (int i = 8; i < 14; i++) {
+                       clk_seq_hi_res.set(i - 8, clockSequenceBits.get(i));
+               }
+               // variant
+               clk_seq_hi_res.set(6, false);
+               clk_seq_hi_res.set(7, true);
+
+//             String str = toHexString(time_low.toLongArray()[0]) + "-" + toHexString(time_mid.toLongArray()[0]) + "-"
+//                             + toHexString(time_hi_and_version.toLongArray()[0]) + "-"
+//                             + toHexString(clock_seq_hi_and_reserved.toLongArray()[0]) + toHexString(clock_seq_low.toLongArray()[0])
+//                             + "-" + toHexString(node.toLongArray()[0]);
+//             UUID uuid = UUID.fromString(str);
+
+               BitSet uuidBits = new BitSet(128);
+               for (int i = 0; i < 128; i++) {
+                       if (i < 48)
+                               uuidBits.set(i, node.get(i));
+                       else if (i < 56)
+                               uuidBits.set(i, clk_seq_low.get(i - 48));
+                       else if (i < 64)
+                               uuidBits.set(i, clk_seq_hi_res.get(i - 56));
+                       else if (i < 80)
+                               uuidBits.set(i, time_hi_and_version.get(i - 64));
+                       else if (i < 96)
+                               uuidBits.set(i, time_mid.get(i - 80));
+                       else
+                               uuidBits.set(i, time_low.get(i - 96));
+               }
+
+               long[] uuidLongs = uuidBits.toLongArray();
+               assert uuidLongs.length == 2;
+               UUID uuid = new UUID(uuidLongs[1], uuidLongs[0]);
+
+               // tests
+               assert uuid.node() == node.toLongArray()[0];
+               assert uuid.timestamp() == timeNanos;
+               assert uuid.clockSequence() == clockSequence;
+               assert uuid.version() == 1;
+               assert uuid.variant() == 2;
+               return uuid;
+       }
+
+       public static String toBinaryString(UUID uuid, int charsPerSegment, char separator) {
+               String binaryString = toBinaryString(uuid);
+               StringBuilder sb = new StringBuilder(128 + (128 / charsPerSegment));
+               for (int i = 0; i < binaryString.length(); i++) {
+                       if (i != 0 && i % charsPerSegment == 0)
+                               sb.append(separator);
+                       sb.append(binaryString.charAt(i));
+               }
+               return sb.toString();
+       }
+
+       public static String toBinaryString(UUID uuid) {
+               String most = zeroTo64Chars(Long.toBinaryString(uuid.getMostSignificantBits()));
+               String least = zeroTo64Chars(Long.toBinaryString(uuid.getLeastSignificantBits()));
+               String binaryString = most + least;
+               assert binaryString.length() == 128;
+               return binaryString;
+       }
+
+       private static String zeroTo64Chars(String str) {
+               assert str.length() <= 64;
+               if (str.length() < 64) {
+                       StringBuilder sb = new StringBuilder(64);
+                       for (int i = 0; i < 64 - str.length(); i++)
+                               sb.append('0');
+                       sb.append(str);
+                       return sb.toString();
+               } else
+                       return str;
+       }
+
+       public static String compactToStd(String compact) {
+               if (compact.length() != 32)
+                       throw new IllegalArgumentException(
+                                       "Compact UUID '" + compact + "' has length " + compact.length() + " and not 32.");
+               StringBuilder sb = new StringBuilder(36);
+               for (int i = 0; i < 32; i++) {
+                       if (i == 8 || i == 12 || i == 16 || i == 20)
+                               sb.append('-');
+                       sb.append(compact.charAt(i));
+               }
+               String std = sb.toString();
+               assert std.length() == 36;
+               assert UUID.fromString(std).toString().equals(std);
+               return std;
+       }
+
+       public static UUID compactToUuid(String compact) {
+               return UUID.fromString(compactToStd(compact));
+       }
+
+       public static boolean isRandom(UUID uuid) {
+               return uuid.version() == 4;
+       }
+
+       public static boolean isTimeBased(UUID uuid) {
+               return uuid.version() == 1;
+       }
+
+       public static boolean isTimeBasedRandom(UUID uuid) {
+               if (uuid.version() == 1) {
+                       BitSet node = BitSet.valueOf(new long[] { uuid.node() });
+                       return node.get(0);
+               } else
+                       return false;
+       }
+
+       public static boolean isNameBased(UUID uuid) {
+               return uuid.version() == 3 || uuid.version() == 5;
+       }
+
+       /** Singleton. */
+       private UuidUtils() {
+       }
+
+       public final static void main(String[] args) throws Exception {
+               UUID uuid;
+
+//             uuid = compactToUuid("996b1f5122de4b2f94e49168d32f22d1");
+//             System.out.println(uuid.toString() + ", isRandom=" + isRandom(uuid));
+
+               // warm up before measuring perf
+               for (int i = 0; i < 10; i++) {
+                       UUID.randomUUID();
+                       timeUUID();
+                       timeUUIDwithRandomNode();
+                       timeBasedRandomUUID();
+                       timeBasedUUID();
+               }
+
+               long begin;
+               long duration;
+
+               begin = System.nanoTime();
+               uuid = UUID.randomUUID();
+               duration = System.nanoTime() - begin;
+               System.out.println(uuid.toString() + " in " + duration + " ns, isRandom=" + isRandom(uuid));
+
+               begin = System.nanoTime();
+               uuid = timeUUID();
+               duration = System.nanoTime() - begin;
+               System.out.println(uuid.toString() + " in " + duration + " ns, isTimeBasedRandom=" + isTimeBasedRandom(uuid));
+
+               begin = System.nanoTime();
+               uuid = timeUUIDwithRandomNode();
+               duration = System.nanoTime() - begin;
+               System.out.println(uuid.toString() + " in " + duration + " ns, isTimeBasedRandom=" + isTimeBasedRandom(uuid));
+
+               begin = System.nanoTime();
+               uuid = timeBasedUUID();
+               duration = System.nanoTime() - begin;
+               System.out.println(uuid.toString() + " in " + duration + " ns, isTimeBasedRandom=" + isTimeBasedRandom(uuid));
+
+               begin = System.nanoTime();
+               uuid = timeBasedRandomUUID();
+               duration = System.nanoTime() - begin;
+               System.out.println(uuid.toString() + " in " + duration + " ns, isTimeBasedRandom=" + isTimeBasedRandom(uuid));
+//             System.out.println(toBinaryString(uuid, 8, ' '));
+//             System.out.println(toBinaryString(uuid, 16, '\n'));
+       }
+}