/*
* JBoss, Home of Professional Open Source.
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership. Some portions may be licensed
* to Red Hat, Inc. under one or more contributor license agreements.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301 USA.
*/
package org.teiid.core.id;
import java.io.Serializable;
/**
* <p>This class represents a universally unique identifier, consisting of
* two long integral values. </p>
*
* <p>This identifier is supposed to be unique both spatially and temporally.
* It is based on version 4 IETF variant random UUIDs. </p>
*/
public class UUID implements Serializable {
private static final long serialVersionUID = 4730187208307761197L;
char DELIMITER = ':';
/**
* The variants allowed by the UUID specification.
*/
class Variant {
public static final int NSC_COMPATIBLE = 0;
public static final int STANDARD = 2;
public static final int MICROSOFT = 6;
public static final int RESERVED_FUTURE = 7;
}
class Version {
public static final int TIME_BASED = 1;
public static final int DCE_RESERVED = 2;
public static final int NAME_BASED = 3;
public static final int PSEUDO_RANDOM = 4;
}
public static final String PROTOCOL = "mmuuid"; //$NON-NLS-1$
public static final String PROTOCOL_UCASE = PROTOCOL.toUpperCase();
private static final int ID_STRING_LEN = 36;
public static final int FQ_LENGTH = PROTOCOL.length() + 1 + ID_STRING_LEN;
private final java.util.UUID uuid;
private String cachedExportableFormUuidString;
/**
* Construct an instance of this class from two long integral values.
* Both values must be non-negative.
* @throws IllegalArgumentException if either value is negative
*/
public UUID( long mostSig, long leastSig ) {
this.uuid = new java.util.UUID(mostSig, leastSig);
}
public UUID(java.util.UUID uuid) {
this.uuid = uuid;
}
/**
* Return the name of the protocol that this factory uses.
* @return the protocol name
*/
public String getProtocol() {
return PROTOCOL;
}
/**
* Returns the hashcode for this instance. All of the bits in each 32-bit
* part of the longs are exclusively 'or'd together to yield the hashcode.
*/
public int hashCode() {
return uuid.hashCode();
}
/**
* <p>Returns true if the specified object is semantically equal to this
* instance. Note: this method is consistent with <code>compareTo()
* </code>. </p>
* <p>UUID instances are equal if they represent the same 128-bit value. </p>
* @param obj the object that this instance is to be compared to.
* @return whether the object is equal to this object.
*/
public boolean equals(Object obj) {
// Check if instances are identical ...
if ( this == obj ) {
return true;
}
// Check if object can be compared to this one
// (this includes checking for null ) ...
if ( obj instanceof UUID ) {
UUID that = (UUID) obj;
return this.uuid.equals(that.uuid);
}
// Otherwise not comparable ...
return false;
}
/**
* <p>Compares this object to another. If the specified object is
* not an instance of the LongID class, then this method throws a
* ClassCastException (as instances are comparable only to instances
* of the same class). </p>
*
* <p>Note: this method <i>is</i> consistent with <code>equals()</code>,
* meaning that <code>(compare(x, y)==0) == (x.equals(y))</code>. </p>
*
* @param obj the object that this instance is to be compared to; may not be null.
* @return a negative integer, zero, or a positive integer as this object
* is less than, equal to, or greater than the specified object, respectively.
* @throws ClassCastException if the specified object's type prevents it
* from being compared to this instance.
*/
public int compareTo(Object obj) {
UUID that = (UUID) obj; // May throw ClassCastException
return this.uuid.compareTo(that.uuid);
}
/**
* Returns a string representing the current state of the object.
* @return the string representation of this instance.
*/
public String toString(){
return toString(DELIMITER);
}
/**
* @see org.teiid.core.id.ObjectID#toString(char)
*/
public String toString(char delim) {
return new StringBuffer(43).append(PROTOCOL).append(delim).append(this.exportableForm()).toString();
}
/**
* <p>Returns a 36-character string of six fields separated by hyphens,
* with each field represented in lowercase hexadecimal with the same
* number of digits as in the field. The order of fields is: time_low,
* time_mid, version and time_hi treated as a single field, variant and
* clock_seq treated as a single field, and node. </p>
*
* @return A string of the form 'xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx',
* where all the characters are lowercase hexadecimal digits
*/
public String exportableForm() {
if (this.cachedExportableFormUuidString == null) {
this.cachedExportableFormUuidString = this.uuid.toString();
}
return this.cachedExportableFormUuidString;
}
public static void main(String[] args) {
System.out.println(new UUID(java.util.UUID.randomUUID()));
}
}