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.asn1.codec.stateful.examples; 021 022 023 import java.nio.ByteBuffer; 024 025 import org.apache.directory.shared.asn1.codec.EncoderException; 026 import org.apache.directory.shared.asn1.codec.stateful.EncoderCallback; 027 import org.apache.directory.shared.asn1.codec.stateful.EncoderMonitor; 028 import org.apache.directory.shared.asn1.codec.stateful.EncoderMonitorAdapter; 029 import org.apache.directory.shared.asn1.codec.stateful.StatefulEncoder; 030 031 032 /** 033 * Document me. 034 * 035 * @author <a href="mailto:dev@directory.apache.org"> Apache Directory Project</a> 036 * @version $Rev: 664290 $ 037 */ 038 public class HexEncoder implements StatefulEncoder 039 { 040 private static final int CHUNK_SZ = 128; 041 042 private ByteBuffer buf = ByteBuffer.allocate( CHUNK_SZ ); 043 044 private EncoderMonitor monitor = new EncoderMonitorAdapter(); 045 046 private EncoderCallback cb = new EncoderCallback() 047 { 048 public void encodeOccurred( StatefulEncoder encoder, Object encoded ) 049 { 050 } 051 }; 052 053 private final byte[] HEXCHAR_LUT = 054 { ( byte ) '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' }; 055 056 057 /** 058 * Transforms a decoded ByteArray of binary data into a stream of ASCII hex 059 * characters. 060 * 061 * @param obj 062 * @throws org.apache.directory.shared.asn1.codec.EncoderException 063 */ 064 public void encode( Object obj ) throws EncoderException 065 { 066 ByteBuffer raw = ( ByteBuffer ) obj; 067 068 if ( raw == null || !raw.hasRemaining() ) 069 { 070 return; 071 } 072 073 /* 074 * Keep encoding one byte at a time if we have remaining bytes in the 075 * raw buffer and there's space for 2 hex character bytes in the 076 * resultant hex encoded buffer. 077 */ 078 while ( raw.hasRemaining() ) 079 { 080 if ( !buf.hasRemaining() ) 081 { 082 buf.flip(); 083 cb.encodeOccurred( this, buf ); 084 monitor.callbackOccured( this, cb, buf ); 085 buf.clear(); 086 } 087 088 byte bite = raw.get(); 089 buf.put( HEXCHAR_LUT[( bite >> 4 ) & 0x0000000F] ); 090 buf.put( HEXCHAR_LUT[bite & 0x0000000F] ); 091 } 092 093 buf.flip(); 094 cb.encodeOccurred( this, buf ); 095 monitor.callbackOccured( this, cb, buf ); 096 buf.clear(); 097 } 098 099 100 public void setCallback( EncoderCallback cb ) 101 { 102 EncoderCallback old = this.cb; 103 this.cb = cb; 104 monitor.callbackSet( this, old, cb ); 105 } 106 107 108 public void setEncoderMonitor( EncoderMonitor monitor ) 109 { 110 this.monitor = monitor; 111 } 112 }