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.asn1.ber.tlv;
021
022
023import org.apache.directory.api.i18n.I18n;
024import org.apache.directory.api.util.Strings;
025import org.slf4j.Logger;
026import org.slf4j.LoggerFactory;
027
028
029/**
030 * Parse and decode a Boolean value.
031 *
032 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
033 */
034public final class BooleanDecoder
035{
036    /** The logger */
037    private static final Logger LOG = LoggerFactory.getLogger( BooleanDecoder.class );
038
039
040    /**
041     * Parse a Value containing a byte[] and send back a boolean.
042     *
043     * @param value The Value to parse
044     * @return A boolean.
045     * @throws BooleanDecoderException Thrown if the Value does not contains a boolean
046     */
047    public static boolean parse( BerValue value ) throws BooleanDecoderException
048    {
049        byte[] bytes = value.getData();
050
051        if ( Strings.isEmpty( bytes ) )
052        {
053            throw new BooleanDecoderException( I18n.err( I18n.ERR_00034_0_BYTES_LONG_BOOLEAN ) );
054        }
055
056        if ( bytes.length != 1 )
057        {
058            throw new BooleanDecoderException( I18n.err( I18n.ERR_00035_N_BYTES_LONG_BOOLEAN ) );
059        }
060
061        if ( ( bytes[0] != 0 ) && ( bytes[0] != ( byte ) 0xFF ) )
062        {
063            LOG.warn( "A boolean must be encoded with a 0x00 or a 0xFF value" );
064        }
065
066        return bytes[0] != 0;
067    }
068}