001    /*
002     *  Licensed to the Apache Software Foundation (ASF) under one
003     *  or more contributor license agreements.  See the NOTICE file
004     *  distributed with this work for additional information
005     *  regarding copyright ownership.  The ASF licenses this file
006     *  to you under the Apache License, Version 2.0 (the
007     *  "License"); you may not use this file except in compliance
008     *  with the License.  You may obtain a copy of the License at
009     *  
010     *    http://www.apache.org/licenses/LICENSE-2.0
011     *  
012     *  Unless required by applicable law or agreed to in writing,
013     *  software distributed under the License is distributed on an
014     *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015     *  KIND, either express or implied.  See the License for the
016     *  specific language governing permissions and limitations
017     *  under the License. 
018     *  
019     */
020    package org.apache.directory.shared.ldap.schema.syntaxCheckers;
021    
022    import org.apache.directory.shared.ldap.constants.SchemaConstants;
023    import org.apache.directory.shared.ldap.schema.SyntaxChecker;
024    import org.apache.directory.shared.ldap.util.StringTools;
025    import org.slf4j.Logger;
026    import org.slf4j.LoggerFactory;
027    
028    
029    /**
030     * An UUID syntax checker.
031     * 
032     * UUID ::= OCTET STRING (SIZE(16)) -- constrained to an UUID [RFC4122]
033     * 
034     * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
035     * @version $Rev: 736240 $
036     */
037    public class UuidSyntaxChecker extends SyntaxChecker
038    {
039        /** A logger for this class */
040        private static final Logger LOG = LoggerFactory.getLogger( UuidSyntaxChecker.class );
041    
042        /** The serialVersionUID */
043        private static final long serialVersionUID = 1L;
044    
045        // Tells if the byte is alphanumeric
046        private static boolean isHex( byte b )
047        {
048            return ( b > 0 ) && StringTools.ALPHA_DIGIT[b];
049        }
050    
051        /**
052         * Creates a new instance of UUIDSyntaxChecker.
053         */
054        public UuidSyntaxChecker()
055        {
056            super( SchemaConstants.UUID_SYNTAX );
057        }
058    
059    
060        /**
061         * {@inheritDoc}
062         */
063        public boolean isValidSyntax( Object value )
064        {
065            if ( value == null )
066            {
067                LOG.debug( "Syntax invalid for '{}'", value );
068                return false;
069            }
070     
071            if ( ! ( value instanceof String ) )
072            {
073                LOG.debug( "Syntax invalid for '{}'", value );
074                return false;
075            }
076    
077            byte[] b = ((String)value).getBytes();
078            
079            if ( b.length < 36)
080            {
081                return false;
082            }
083            
084            if ( 
085                isHex( b[0] ) && isHex( b[1] ) && isHex( b[2] ) && isHex( b[3] ) &
086                isHex( b[4] ) && isHex( b[5] ) && isHex( b[6] ) && isHex( b[7] ) &
087                b[8] == '-' &
088                isHex( b[9] ) && isHex( b[10] ) && isHex( b[11] ) && isHex( b[12] ) &
089                b[13] == '-' &
090                isHex( b[14] ) && isHex( b[15] ) && isHex( b[16] ) && isHex( b[17] ) &
091                b[18] == '-' &
092                isHex( b[19] ) && isHex( b[20] ) && isHex( b[21] ) && isHex( b[22] ) &
093                b[23] == '-' &
094                isHex( b[24] ) && isHex( b[25] ) && isHex( b[26] ) && isHex( b[27] ) &
095                isHex( b[28] ) && isHex( b[29] ) && isHex( b[30] ) && isHex( b[31] ) &
096                isHex( b[32] ) && isHex( b[33] ) && isHex( b[34] ) && isHex( b[35] ) )
097            {
098                // There is not that much more we can check.
099                LOG.debug( "Syntax valid for '{}'", value );
100                return true;
101            }
102    
103            LOG.debug( "Syntax invalid for '{}'", value );
104            return false;
105        }
106    }