UUID_nil.java

/*
 * 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 org.apache.jena.shared.uuid;

/** The nil UUID.  There is only one in the system.
 */

public final
class UUID_nil extends JenaUUID
{
    private static final String nilStr = "00000000-0000-0000-0000-000000000000" ;
    private static UUID_nil nil = new UUID_nil() ;
    
    // Constants
    static final int version = 0 ;
    static final int variant = 0 ;

    // The only state-per-object
    long bitsMostSignificant = 0 ;
    long bitsLeastSignificant = 0 ;
    
    private UUID_nil()
    {}
    
    
    @Override
    public long getMostSignificantBits() { return bitsMostSignificant ; }
    @Override
    public long getLeastSignificantBits() { return bitsLeastSignificant ; }
    
    @Override
    public String toString()
    { return nilStr ; }

    @Override
    public boolean equals(Object other)
    {
        if ( ! ( other instanceof UUID_nil ) )
            return false ;
        UUID_nil x = (UUID_nil)other ;
        return this.bitsMostSignificant == x.bitsMostSignificant &&  this.bitsLeastSignificant == x.bitsLeastSignificant ;
    }


    @Override
    public int getVariant() { return variant ; }
    @Override
    public int getVersion() { return version ; }
    
    public static UUID_nil getNil() { return nil ; }
    public static String  getNilString() { return nilStr ; }
}