org.tiogasolutions.dev.common.id.uuid.TimeUuid Maven / Gradle / Ivy
/*
* UUID.java
*
* Created 07.02.2003
*
* eaio: UUID - an implementation of the UUID specification
* Copyright (c) 2003-2013 Johann Burkard ([email protected]) http://eaio.com.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
* NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
* USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
package org.tiogasolutions.dev.common.id.uuid;
import java.io.*;
import org.omg.CORBA.portable.IDLEntity;
/**
* Creates UUIDs according to the DCE Universal Token Identifier specification.
*
* All you need to know:
*
* UUID u = new UUID();
*
*
* @see
* http://www.opengroup.org/onlinepubs/9629399/apdxa.htm
*
* @see
* http://www.uddi.org/pubs/draft-leach-uuids-guids-01.txt
*
* @see UUID
* @author Johann Burkard
* @version $Id: UUID.java 4688 2012-03-09 14:49:49Z johann $
*/
public class TimeUuid implements Comparable, Externalizable, Cloneable, IDLEntity {
private static final long serialVersionUID = 1L;
public static TimeUuid randomUUID() {
return new TimeUuid();
}
/**
* The time field of the UUID.
*
* @serial
*/
public long time;
/**
* The clock sequence and node field of the UUID.
*
* @serial
*/
public long clockSeqAndNode;
/**
* Constructor for UUID. Constructs a new, unique UUID.
*
* @see TimeUuidFactory#newTime()
* @see TimeUuidFactory#getClockSeqAndNode()
*/
public TimeUuid() {
this(TimeUuidFactory.newTime(), TimeUuidFactory.getClockSeqAndNode());
}
/**
* Constructor for UUID. Constructs a UUID from two long values.
*
* @param time the upper 64 bits
* @param clockSeqAndNode the lower 64 bits
*/
public TimeUuid(long time, long clockSeqAndNode) {
this.time = time;
this.clockSeqAndNode = clockSeqAndNode;
}
/**
* Copy constructor for UUID. Values of the given UUID are copied.
*
* @param u the UUID, may not be null
*/
public TimeUuid(TimeUuid u) {
this(u.time, u.clockSeqAndNode);
}
/**
* Parses a textual representation of a UUID.
*
* No validation is performed. If the {@link CharSequence} is shorter than 36 characters,
* {@link ArrayIndexOutOfBoundsException}s will be thrown.
*
* @param s the {@link CharSequence}, may not be null
*/
public TimeUuid(CharSequence s) {
this(TimeUuidHexUtil.parseLong(s.subSequence(0, 18)), TimeUuidHexUtil.parseLong(s.subSequence(
19, 36)));
}
/**
* Compares this UUID to another Object. Throws a {@link ClassCastException} if
* the other Object is not an instance of the UUID class. Returns a value
* smaller than zero if the other UUID is "larger" than this UUID and a value
* larger than zero if the other UUID is "smaller" than this UUID.
*
* @param t the other UUID, may not be null
* @return a value < 0, 0 or a value > 0
* @see java.lang.Comparable#compareTo(java.lang.Object)
*/
public int compareTo(TimeUuid t) {
if (this == t) {
return 0;
}
if (time > t.time) {
return 1;
}
if (time < t.time) {
return -1;
}
if (clockSeqAndNode > t.clockSeqAndNode) {
return 1;
}
if (clockSeqAndNode < t.clockSeqAndNode) {
return -1;
}
return 0;
}
/**
* Tweaked Serialization routine.
*/
public void writeExternal(ObjectOutput out) throws IOException {
out.writeLong(time);
out.writeLong(clockSeqAndNode);
}
/**
* Tweaked Serialization routine.
*/
public void readExternal(ObjectInput in) throws IOException {
time = in.readLong();
clockSeqAndNode = in.readLong();
}
/**
* Returns this UUID as a String.
*
* @return a String, never null
* @see java.lang.Object#toString()
* @see #toAppendable(Appendable)
*/
@Override
public final String toString() {
return toAppendable(null).toString();
}
/**
* Appends a String representation of this to the given {@link StringBuffer} or
* creates a new one if none is given.
*
* @param in the StringBuffer to append to, may be null
* @return a StringBuffer, never null
* @see #toAppendable(Appendable)
*/
public StringBuffer toStringBuffer(StringBuffer in) {
StringBuffer out = in;
if (out == null) {
out = new StringBuffer(36);
}
else {
out.ensureCapacity(out.length() + 36);
}
return (StringBuffer) toAppendable(out);
}
/**
* Appends a String representation of this object to the given {@link Appendable} object.
*
* For reasons I'll probably never understand, Sun has decided to have a number of I/O classes implement
* Appendable which forced them to destroy an otherwise nice and simple interface with {@link IOException}s.
*
* I decided to ignore any possible IOExceptions in this method.
*
* @param a the Appendable object, may be null
* @return an Appendable object, defaults to a {@link StringBuilder} if a is null
*/
public Appendable toAppendable(Appendable a) {
Appendable out = a;
if (out == null) {
out = new StringBuilder(36);
}
try {
TimeUuidHexUtil.append(out, (int) (time >> 32)).append('-');
TimeUuidHexUtil.append(out, (short) (time >> 16)).append('-');
TimeUuidHexUtil.append(out, (short) time).append('-');
TimeUuidHexUtil.append(out, (short) (clockSeqAndNode >> 48)).append('-');
TimeUuidHexUtil.append(out, clockSeqAndNode, 12);
}
catch (IOException ex) {
// What were they thinking?
}
return out;
}
/**
* Returns a hash code of this UUID. The hash code is calculated by XOR'ing the
* upper 32 bits of the time and clockSeqAndNode fields and the lower 32 bits of
* the time and clockSeqAndNode fields.
*
* @return an int representing the hash code
* @see java.lang.Object#hashCode()
*/
@Override
public int hashCode() {
return (int) ((time >> 32) ^ time ^ (clockSeqAndNode >> 32) ^ clockSeqAndNode);
}
/**
* Clones this UUID.
*
* @return a new UUID with identical values, never null
*/
@Override
public Object clone() {
try {
return super.clone();
}
catch (CloneNotSupportedException ex) {
// One of Sun's most epic fails.
return null;
}
}
/**
* Returns the time field of the UUID (upper 64 bits).
*
* @return the time field
*/
public final long getTime() {
return time;
}
/**
* Returns the clock and node field of the UUID (lower 64 bits).
*
* @return the clockSeqAndNode field
*/
public final long getClockSeqAndNode() {
return clockSeqAndNode;
}
/**
* Compares two Objects for equality.
*
* @see java.lang.Object#equals(Object)
* @param obj the Object to compare this UUID with, may be null
* @return true if the other Object is equal to this UUID,
* false if not
*/
@Override
public boolean equals(Object obj) {
if (!(obj instanceof TimeUuid)) {
return false;
}
return compareTo((TimeUuid) obj) == 0;
}
/**
* Returns the nil UUID (a UUID whose values are both set to zero).
*
* Starting with version 2.0, this method does return a new UUID instance every
* time it is called. Earlier versions returned one instance. This has now been
* changed because this UUID has public, non-final instance fields. Returning a
* new instance is therefore more safe.
*
* @return a nil UUID, never null
*/
public static TimeUuid nilUUID() {
return new TimeUuid(0, 0);
}
}