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    
023    import java.util.regex.Pattern;
024    
025    import org.apache.directory.shared.ldap.constants.SchemaConstants;
026    import org.apache.directory.shared.ldap.schema.SyntaxChecker;
027    import org.apache.directory.shared.ldap.util.StringTools;
028    import org.slf4j.Logger;
029    import org.slf4j.LoggerFactory;
030    
031    
032    /**
033     * A SyntaxChecker which verifies that a value is a UTC time
034     * according to RFC 4517.
035     * 
036     * From RFC 4517 :
037     * UTCTime         = year month day hour minute [ second ] [ u-time-zone ]
038     * u-time-zone     = %x5A          ; "Z" | u-differential
039     * u-differential  = ( MINUS | PLUS ) hour minute
040     *
041     * year    = 2(%x30-39)            ; "00" to "99"
042     * month   = ( %x30 %x31-39 )      ; "01" (January) to "09"
043     *           | ( %x31 %x30-32 )    ; "10" to "12"
044     * day     = ( %x30 %x31-39 )      ; "01" to "09"
045     *           | ( %x31-32 %x30-39 ) ; "10" to "29"
046     *           | ( %x33 %x30-31 )    ; "30" to "31"
047     * hour    = ( %x30-31 %x30-39 ) 
048     *           | ( %x32 %x30-33 )    ; "00" to "23"
049     * minute  = %x30-35 %x30-39       ; "00" to "59"
050     *
051     * second  = ( %x30-35 %x30-39 )   ; "00" to "59"
052     *
053     * g-time-zone = %x5A              ; "Z"
054     *               | g-differential
055     * g-differential = ( MINUS / PLUS ) hour [ minute ]
056     * MINUS   = %x2D  ; minus sign ("-")
057     * 
058     * From RFC 4512 :
059     * PLUS    = %x2B ; plus sign ("+")
060     * 
061     *
062     * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
063     * @version $Rev$
064     */
065    public class UtcTimeSyntaxChecker extends SyntaxChecker
066    {
067        /** A logger for this class */
068        private static final Logger LOG = LoggerFactory.getLogger( UtcTimeSyntaxChecker.class );
069    
070        /** The serialVersionUID */
071        private static final long serialVersionUID = 1L;
072    
073        /** The GeneralizedDate pattern matching */
074        private static final String UTC_TIME_PATTERN = 
075                    "^\\d{2}" +                                 // year : 00 to 99
076                    "(0[1-9]|1[0-2])" +                         // month : 01 to 12
077                    "(0[1-9]|[12]\\d|3[01])" +                  // day : 01 to 31
078                    "([01]\\d|2[0-3])" +                        // hour: 00 to 23
079                    "([0-5]\\d)" +                              // minute : 00 to 59
080                    "(" +
081                        "([0-5]\\d)?" +                         // optional second : 00 to 59
082                        "(Z|([+-]([01]\\d|2[0-3])[0-5]\\d))?" + // optionnal time-zone
083                    ")$";
084        
085        // The regexp pattern matcher
086        private Pattern datePattern = Pattern.compile( UTC_TIME_PATTERN ); 
087    
088        /**
089         * 
090         * Creates a new instance of UtcTimeSyntaxChecker.
091         *
092         */
093        public UtcTimeSyntaxChecker()
094        {
095            super( SchemaConstants.UTC_TIME_SYNTAX );
096        }
097        
098        
099        /**
100         * {@inheritDoc}
101         */
102        public boolean isValidSyntax( Object value )
103        {
104            String strValue = null;
105    
106            if ( value == null )
107            {
108                LOG.debug( "Syntax invalid for '{}'", value );
109                return false;
110            }
111            
112            if ( value instanceof String )
113            {
114                strValue = ( String ) value;
115            }
116            else if ( value instanceof byte[] )
117            {
118                strValue = StringTools.utf8ToString( ( byte[] ) value ); 
119            }
120            else
121            {
122                strValue = value.toString();
123            }
124    
125            // A generalized time must have a minimal length of 11 
126            if ( strValue.length() < 11 )
127            {
128                LOG.debug( "Syntax invalid for '{}'", value );
129                return false;
130            }
131            
132            // Start the date parsing
133            boolean result = datePattern.matcher( strValue ).find();
134            
135            if ( result )
136            {
137                LOG.debug( "Syntax valid for '{}'", value );
138            }
139            else
140            {
141                LOG.debug( "Syntax invalid for '{}'", value );
142            }
143            return result;
144        }
145    }