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.i18n.I18n;
024import org.apache.directory.api.ldap.model.constants.SchemaConstants;
025import org.apache.directory.api.ldap.model.schema.SyntaxChecker;
026import org.apache.directory.api.util.Chars;
027import org.apache.directory.api.util.Strings;
028
029
030/**
031 * A SyntaxChecker which verifies that a value is an Integer according to RFC 4517.
032 * 
033 * From RFC 4517 :
034 * 
035 * <pre>
036 * Integer = ( HYPHEN LDIGIT *DIGIT ) | number
037 * 
038 * From RFC 4512 :
039 * number  = DIGIT | ( LDIGIT 1*DIGIT )
040 * DIGIT   = %x30 | LDIGIT       ; "0"-"9"
041 * LDIGIT  = %x31-39             ; "1"-"9"
042 * HYPHEN  = %x2D                ; hyphen ("-")
043 * </pre>
044 *
045 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
046 */
047@SuppressWarnings("serial")
048public final class IntegerSyntaxChecker extends SyntaxChecker
049{
050    /**
051     * A static instance of IntegerSyntaxChecker
052     */
053    public static final IntegerSyntaxChecker INSTANCE = new IntegerSyntaxChecker( SchemaConstants.INTEGER_SYNTAX );
054    
055    /**
056     * A static Builder for this class
057     */
058    public static final class Builder extends SCBuilder<IntegerSyntaxChecker>
059    {
060        /**
061         * The Builder constructor
062         */
063        private Builder()
064        {
065            super( SchemaConstants.INTEGER_SYNTAX );
066        }
067        
068        
069        /**
070         * Create a new instance of IntegerSyntaxChecker
071         * @return A new instance of IntegerSyntaxChecker
072         */
073        @Override
074        public IntegerSyntaxChecker build()
075        {
076            return new IntegerSyntaxChecker( oid );
077        }
078    }
079
080    
081    /**
082     * Creates a new instance of IntegerSyntaxChecker.
083     * 
084     * @param oid The OID to use for this SyntaxChecker
085     */
086    private IntegerSyntaxChecker( String oid )
087    {
088        super( oid );
089    }
090
091    
092    /**
093     * @return An instance of the Builder for this class
094     */
095    public static Builder builder()
096    {
097        return new Builder();
098    }
099
100
101    /**
102     * {@inheritDoc}
103     */
104    @Override
105    public boolean isValidSyntax( Object value )
106    {
107        String strValue;
108
109        if ( value == null )
110        {
111            if ( LOG.isDebugEnabled() )
112            {
113                LOG.debug( I18n.err( I18n.ERR_04488_SYNTAX_INVALID, "null" ) );
114            }
115            
116            return false;
117        }
118
119        if ( value instanceof String )
120        {
121            strValue = ( String ) value;
122        }
123        else if ( value instanceof byte[] )
124        {
125            strValue = Strings.utf8ToString( ( byte[] ) value );
126        }
127        else
128        {
129            strValue = value.toString();
130        }
131
132        if ( strValue.length() == 0 )
133        {
134            if ( LOG.isDebugEnabled() )
135            {
136                LOG.debug( I18n.err( I18n.ERR_04488_SYNTAX_INVALID, value ) );
137            }
138            
139            return false;
140        }
141
142        // The first char must be either a '-' or in [0..9].
143        // If it's a '0', then there should be any other char after
144        int pos = 0;
145        char c = strValue.charAt( pos );
146
147        if ( c == '-' )
148        {
149            pos = 1;
150        }
151        else if ( !Chars.isDigit( c ) )
152        {
153            if ( LOG.isDebugEnabled() )
154            {
155                LOG.debug( I18n.err( I18n.ERR_04488_SYNTAX_INVALID, value ) );
156            }
157            
158            return false;
159        }
160        else if ( c == '0' )
161        {
162            if ( strValue.length() > 1 )
163            {
164                if ( LOG.isDebugEnabled() )
165                {
166                    LOG.debug( I18n.err( I18n.ERR_04488_SYNTAX_INVALID, value ) );
167                }
168                
169                return false;
170            }
171            else
172            {
173                if ( LOG.isDebugEnabled() )
174                {
175                    LOG.debug( I18n.msg( I18n.MSG_04489_SYNTAX_VALID, value ) );
176                }
177                
178                return true;
179            }
180        }
181
182        // We must have at least a digit which is not '0'
183        if ( !Chars.isDigit( strValue, pos ) || Strings.isCharASCII( strValue, pos, '0' ) )
184        {
185            if ( LOG.isDebugEnabled() )
186            {
187                LOG.debug( I18n.err( I18n.ERR_04488_SYNTAX_INVALID, value ) );
188            }
189            
190            return false;
191        }
192        else
193        {
194            pos++;
195        }
196
197        while ( Chars.isDigit( strValue, pos ) )
198        {
199            pos++;
200        }
201
202        boolean result = pos == strValue.length();
203
204        if ( LOG.isDebugEnabled() )
205        {
206            if ( result )
207            {
208                LOG.debug( I18n.msg( I18n.MSG_04489_SYNTAX_VALID, value ) );
209            }
210            else
211            {
212                LOG.debug( I18n.err( I18n.ERR_04488_SYNTAX_INVALID, value ) );
213            }
214        }
215
216        return result;
217    }
218}