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.HashSet;
024    import java.util.Set;
025    
026    import org.apache.directory.shared.ldap.constants.SchemaConstants;
027    import org.apache.directory.shared.ldap.schema.SyntaxChecker;
028    import org.apache.directory.shared.ldap.util.StringTools;
029    import org.slf4j.Logger;
030    import org.slf4j.LoggerFactory;
031    
032    
033    /**
034     * A SyntaxChecker which verifies that a value is a delivery method 
035     * according to RFC 4517.
036     * 
037     * From RFC 4517 & RFC 4512:
038     * 
039     * DeliveryMethod = pdm *( WSP DOLLAR WSP pdm )
040     *
041     * pdm = "any" | "mhs" | "physical" | "telex" | "teletex" |
042     *       "g3fax" | "g4fax" | "ia5" | "videotex" | "telephone"
043     *           
044     * WSP     = 0*SPACE  ; zero or more " "
045     * DOLLAR  = %x24 ; dollar sign ("$")
046     * SPACE   = %x20 ; space (" ")
047     * 
048     *
049     * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
050     * @version $Rev$
051     */
052    public class DeliveryMethodSyntaxChecker extends SyntaxChecker
053    {
054        /** A logger for this class */
055        private static final Logger LOG = LoggerFactory.getLogger( DeliveryMethodSyntaxChecker.class );
056    
057        /** The serialVersionUID */
058        private static final long serialVersionUID = 1L;
059    
060        private static final String[] PDMS = 
061            {
062                "any", "mhs", "physical", "telex", "teletex",
063                "g3fax", "g4fax", "ia5", "videotex", "telephone"
064            };
065    
066        /** The Set which contains the delivery methods */
067        private static final Set<String> DELIVERY_METHODS = new HashSet<String>();
068        
069        /** Initialization of the delivery methods set */
070        static
071        {
072            for ( String country:PDMS )
073            {
074                DELIVERY_METHODS.add( country );
075            }
076        }
077        
078        /**
079         * 
080         * Creates a new instance of DeliveryMethodSyntaxChecker.
081         *
082         */
083        public DeliveryMethodSyntaxChecker()
084        {
085            super( SchemaConstants.DELIVERY_METHOD_SYNTAX );
086        }
087        
088        
089        /**
090         * 
091         * Check if the string contains a delivery method which has 
092         * not already been found.
093         * 
094         * @param strValue The string we want to look into for a PDM 
095         * @param pos The current position in the string
096         * @param pdms The set containing all the PDM
097         * @return if a Prefered Delivery Method is found in the given string, returns 
098         * its position, otherwise, returns -1
099         */
100        private int isPdm( String strValue, int start, Set<String> pdms )
101        {
102            int pos = start;
103            
104            while ( StringTools.isAlphaDigit( strValue, pos ) )
105            {
106                pos++;
107            }
108            
109            // No ascii string, this is not a delivery method
110            if ( pos == start )
111            {
112                return -1;
113            }
114            
115            String pdm = strValue.substring( start, pos );
116            
117            if ( ! DELIVERY_METHODS.contains( pdm ) )
118            {
119                // The delivery method is unknown
120                return -1;
121            }
122            else
123            {
124                if ( pdms.contains( pdm ) )
125                {
126                    // The delivery method has already been found
127                    return -1;
128                }
129                else
130                {
131                    pdms.add( pdm );
132                    return pos;
133                }
134            }
135        }
136    
137    
138        /**
139         * {@inheritDoc}
140         */
141        public boolean isValidSyntax( Object value )
142        {
143            String strValue = null;
144    
145            if ( value == null )
146            {
147                LOG.debug( "Syntax invalid for '{}'", value );
148                return false;
149            }
150            
151            if ( value instanceof String )
152            {
153                strValue = ( String ) value;
154            }
155            else if ( value instanceof byte[] )
156            {
157                strValue = StringTools.utf8ToString( ( byte[] ) value ); 
158            }
159            else
160            {
161                strValue = value.toString();
162            }
163    
164            if ( strValue.length() == 0 )
165            {
166                LOG.debug( "Syntax invalid for '{}'", value );
167                return false;
168            }
169            
170            // We will get the first delivery method
171            int length = strValue.length();
172            int pos = 0;
173            Set<String> pmds = new HashSet<String>();
174                
175            if ( ( pos = isPdm( strValue, pos, pmds ) ) == -1)
176            {
177                LOG.debug( "Syntax invalid for '{}'", value );
178                return false;
179            }
180            
181            // We have found at least the first pmd,
182            // now iterate through the other ones. We may have
183            // SP* '$' SP* before each pmd.
184            while ( pos < length )
185            {
186                // Skip spaces
187                while ( StringTools.isCharASCII( strValue, pos, ' ' ) )
188                {
189                    pos++;
190                }
191                
192                if ( ! StringTools.isCharASCII( strValue, pos, '$' ) )
193                {
194                    // A '$' was expected
195                    LOG.debug( "Syntax invalid for '{}'", value );
196                    return false;
197                }
198                else
199                {
200                    pos++;
201                }
202                
203                // Skip spaces
204                while ( StringTools.isCharASCII( strValue, pos, ' ' ) )
205                {
206                    pos++;
207                }
208    
209                if ( ( pos = isPdm( strValue, pos, pmds ) ) == -1 )
210                {
211                    LOG.debug( "Syntax invalid for '{}'", value );
212                    return false;
213                }
214            }
215    
216            LOG.debug( "Syntax valid for '{}'", value );
217            return true;
218        }
219    }