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 */
020package org.apache.directory.shared.ldap.model.schema.syntaxCheckers;
021
022
023import org.apache.directory.shared.ldap.model.constants.SchemaConstants;
024import org.apache.directory.shared.ldap.model.schema.SyntaxChecker;
025import org.apache.directory.shared.util.Strings;
026import org.slf4j.Logger;
027import org.slf4j.LoggerFactory;
028
029
030/**
031 * A SyntaxChecker which verifies that a value is a Directory String according to RFC 4517.
032 * 
033 * From RFC 4517 :
034 * DirectoryString = 1*UTF8
035 * 
036 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
037 */
038@SuppressWarnings("serial")
039public class DirectoryStringSyntaxChecker extends SyntaxChecker
040{
041    /** A logger for this class */
042    private static final Logger LOG = LoggerFactory.getLogger( DirectoryStringSyntaxChecker.class );
043
044    /**
045     * Creates a new instance of DirectoryStringSyntaxChecker.
046     */
047    public DirectoryStringSyntaxChecker()
048    {
049        super( SchemaConstants.DIRECTORY_STRING_SYNTAX );
050    }
051    
052    
053    /**
054     * {@inheritDoc}
055     */
056    public boolean isValidSyntax( Object value )
057    {
058        String strValue = null;
059
060        if ( value == null )
061        {
062            LOG.debug( "Syntax invalid for 'null'" );
063            return false;
064        }
065        
066        if ( value instanceof String )
067        {
068            strValue = ( String ) value;
069        }
070        else if ( value instanceof byte[] )
071        {
072            strValue = Strings.utf8ToString((byte[]) value);
073        }
074        else
075        {
076            strValue = value.toString();
077        }
078
079        // If the value was an invalid UTF8 string, then it's length
080        // will be 0 as the StringTools.utf8ToString() call will
081        // return an empty string
082        if ( strValue.length() == 0 )
083        {
084            LOG.debug( "Syntax invalid for '{}'", value );
085            return false;
086        }
087        
088        // In any other case, we have to check that the
089        // string does not contains the '0xFFFD' character
090        for ( char c:strValue.toCharArray() )
091        {
092            if ( c == 0xFFFD )
093            {
094                LOG.debug( "Syntax invalid for '{}'", value );
095                return false;
096            }
097        }
098        
099        LOG.debug( "Syntax valid for '{}'", value );
100        return true;
101    }
102}