/*
* 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.
*/
package com.hp.hpl.jena.shared.uuid;
import java.util.* ;
import com.hp.hpl.jena.shared.uuid.JenaUUID.FormatException;
/** Generator for for random number based UUIDs (version 2, variant 4)
*/
public class UUID_V4_Gen implements UUIDFactory
{
// Implementation should be compatible with JXTA UUIDs
static final int versionHere = 4 ; // Version 4: random number
static final int variantHere = JenaUUID.Var_Std ;
Random random = null ;
public UUID_V4_Gen() {}
@Override
public JenaUUID generate()
{ return generateV4() ; }
public UUID_V4 generateV4()
{
init() ;
long mostSigBits = random.nextLong() ;
long leastSigBits = random.nextLong() ;
mostSigBits = Bits.pack(mostSigBits, versionHere, 12, 16) ;
leastSigBits = Bits.pack(leastSigBits, variantHere, 62, 64) ;
return new UUID_V4(mostSigBits, leastSigBits) ;
}
@Override
public JenaUUID parse(String s)
{ return parseV4(s) ; }
public UUID_V4 parseV4(String s)
{
s = s.toLowerCase() ;
if ( s.length() != 36 )
throw new FormatException("UUID string is not 36 chars long: it's "+s.length()+" ["+s+"]") ;
if ( s.charAt(8) != '-' && s.charAt(13) != '-' && s.charAt(18) != '-' && s.charAt(23) != '-' )
throw new FormatException("String does not have dashes in the right places: "+s) ;
UUID_V4 u = parse$(s) ;
if ( u.getVersion() != versionHere )
throw new FormatException("Wrong version (Expected: "+versionHere+"Got: "+u.getVersion()+"): "+s) ;
if ( u.getVariant() != variantHere )
throw new FormatException("Wrong version (Expected: "+variantHere+"Got: "+u.getVariant()+"): "+s) ;
return u ;
}
static UUID_V4 parse$(String s)
{
// The UUID broken up into parts.
// 00000000-0000-0000-0000-000000000000
// ^ ^ ^ ^ ^
// Byte: 0 4 6 8 10
// Char: 0 9 14 19 24 including hyphens
long mostSigBits = Bits.unpack(s, 0, 8) ;
// Skip -
mostSigBits = mostSigBits << 16 | Bits.unpack(s, 9, 13) ;
// Skip -
mostSigBits = mostSigBits << 16 | Bits.unpack(s, 14, 18) ;
long leastSigBits = Bits.unpack(s, 19, 23) ;
leastSigBits = leastSigBits<<48 | Bits.unpack(s, 24, 36) ;
return new UUID_V4(mostSigBits, leastSigBits) ;
}
public static String unparse(UUID_V4 uuid)
{
StringBuffer sb = new StringBuffer(36) ;
JenaUUID.toHex(sb, Bits.unpack(uuid.bitsMostSignificant, 32, 64), 4) ;
sb.append('-') ;
JenaUUID.toHex(sb, Bits.unpack(uuid.bitsMostSignificant, 16, 32), 2) ;
sb.append('-') ;
JenaUUID.toHex(sb, Bits.unpack(uuid.bitsMostSignificant, 0, 16), 2) ;
sb.append('-') ;
JenaUUID.toHex(sb, Bits.unpack(uuid.bitsLeastSignificant, 48, 64), 2) ;
sb.append('-') ;
JenaUUID.toHex(sb, Bits.unpack(uuid.bitsLeastSignificant, 0, 48), 6) ;
return sb.toString() ;
}
private void init()
{
if ( random == null )
reset() ;
}
@Override
public void reset()
{
random = LibUUID.makeRandom() ;
}
}