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.api.ldap.model.schema.syntaxCheckers;
021
022
023import org.apache.directory.api.ldap.model.constants.SchemaConstants;
024import org.apache.directory.api.ldap.model.schema.SyntaxChecker;
025import org.apache.directory.api.util.Chars;
026import org.apache.directory.api.util.Strings;
027import org.slf4j.Logger;
028import org.slf4j.LoggerFactory;
029
030
031/**
032 * A SyntaxChecker which verifies that a value is a Boolean according to RFC 4517.
033 * 
034 * From RFC 4512 & RFC 4517 :
035 * 
036 * BitString    = SQUOTE *binary-digit SQUOTE "B"
037 * binary-digit = "0" / "1"
038 * SQUOTE  = %x27                           ; hyphen ("'")
039 * 
040 *
041 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
042 */
043@SuppressWarnings("serial")
044public class BitStringSyntaxChecker extends SyntaxChecker
045{
046    /** A logger for this class */
047    private static final Logger LOG = LoggerFactory.getLogger( BitStringSyntaxChecker.class );
048
049
050    /**
051     * 
052     * Creates a new instance of BitStringSyntaxChecker.
053     *
054     */
055    public BitStringSyntaxChecker()
056    {
057        super( SchemaConstants.BIT_STRING_SYNTAX );
058    }
059
060
061    /**
062     * A shared and static method used to check that the string is a BitString.
063     * A BitString is a string of bits, between quotes and followed by a 'B' :
064     * 
065     * '01010110'B for instance
066     * 
067     * @param strValue The string to check
068     * @return <code>true</code> if the string is a BitString
069     */
070    public static boolean isValid( String strValue )
071    {
072        if ( strValue.length() == 0 )
073        {
074            LOG.debug( "Syntax invalid for '{}'", strValue );
075            return false;
076        }
077
078        int pos = 0;
079
080        // Check that the String respect the syntax : ' ([01]+) ' B
081        if ( !Strings.isCharASCII( strValue, pos++, '\'' ) )
082        {
083            LOG.debug( "Syntax invalid for '{}'", strValue );
084            return false;
085        }
086
087        // We must have at least one bit
088        if ( !Chars.isBit( strValue, pos++ ) )
089        {
090            LOG.debug( "Syntax invalid for '{}'", strValue );
091            return false;
092        }
093
094        while ( Chars.isBit( strValue, pos ) )
095        {
096            // Loop until we get a char which is not a 0 or a 1
097            pos++;
098        }
099
100        // Now, we must have a simple quote 
101        if ( !Strings.isCharASCII( strValue, pos++, '\'' ) )
102        {
103            LOG.debug( "Syntax invalid for '{}'", strValue );
104            return false;
105        }
106
107        // followed by a 'B'
108        if ( !Strings.isCharASCII( strValue, pos, 'B' ) )
109        {
110            LOG.debug( "Syntax invalid for '{}'", strValue );
111            return false;
112        }
113
114        LOG.debug( "Syntax valid for '{}'", strValue );
115        return true;
116    }
117
118
119    /**
120     * {@inheritDoc}
121     */
122    public boolean isValidSyntax( Object value )
123    {
124        String strValue = null;
125
126        if ( value == null )
127        {
128            LOG.debug( "Syntax invalid for 'null'" );
129            return false;
130        }
131
132        if ( value instanceof String )
133        {
134            strValue = ( String ) value;
135        }
136        else if ( value instanceof byte[] )
137        {
138            strValue = Strings.utf8ToString( ( byte[] ) value );
139        }
140        else
141        {
142            strValue = value.toString();
143        }
144
145        return isValid( strValue );
146    }
147}