📄 bencoder.java
字号:
/*
* BEncoder.java
*
* Created on June 4, 2003, 10:17 PM
* Copyright (C) 2003, 2004, 2005, 2006 Aelitis, All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* AELITIS, SAS au capital de 46,603.30 euros
* 8 Allee Lenotre, La Grille Royale, 78600 Le Mesnil le Roi, France.
*/
package org.gudy.azureus2.core3.util;
import java.io.*;
import java.nio.ByteBuffer;
import java.util.*;
/**
* A set of utility methods to encode a Map into a bencoded array of byte.
* integer are represented as Long, String as byte[], dictionnaries as Map, and list as List.
*
* @author TdC_VgA
*/
public class
BEncoder
{
public static byte[] encode(Map object) throws IOException{
ByteArrayOutputStream baos = new ByteArrayOutputStream();
new BEncoder().encode(baos, object);
return baos.toByteArray();
}
private void
encode(
ByteArrayOutputStream baos,
Object object)
throws IOException
{
if ( object instanceof String || object instanceof Float){
String tempString = (object instanceof String) ? (String)object : String.valueOf((Float)object);
ByteBuffer bb = Constants.DEFAULT_CHARSET.encode( tempString );
write(baos,Constants.DEFAULT_CHARSET.encode(String.valueOf(bb.limit())));
baos.write(':');
write(baos,bb );
}else if(object instanceof Map){
Map tempMap = (Map)object;
SortedMap tempTree = null;
// unfortunately there are some occasions where we want to ensure that
// the 'key' of the map is not mangled by assuming its UTF-8 encodable.
// In particular the response from a tracker scrape request uses the
// torrent hash as the KEY. Hence the introduction of the type below
// to allow the constructor of the Map to indicate that the keys should
// be extracted using a BYTE_ENCODING
boolean byte_keys = object instanceof ByteEncodedKeyHashMap;
//write the d
baos.write('d');
//are we sorted?
if ( tempMap instanceof TreeMap ){
tempTree = (TreeMap)tempMap;
}else{
//do map sorting here
tempTree = new TreeMap(tempMap);
}
Iterator it = tempTree.entrySet().iterator();
while( it.hasNext()){
Map.Entry entry = (Map.Entry)it.next();
Object o_key = entry.getKey();
Object value = entry.getValue();
if ( value != null ){
if ( o_key instanceof byte[]){
encode( baos, (byte[])o_key);
encode( baos, value );
}else{
String key = (String)o_key;
if ( byte_keys ){
try{
encode( baos, Constants.BYTE_CHARSET.encode(key));
encode( baos, tempMap.get(key));
}catch( UnsupportedEncodingException e ){
throw( new IOException( "BEncoder: unsupport encoding: " + e.getMessage()));
}
}else{
encode(baos, key ); // Key goes in as UTF-8
encode(baos, value);
}
}
}
}
baos.write('e');
}else if(object instanceof List){
List tempList = (List)object;
//write out the l
baos.write('l');
for(int i = 0; i<tempList.size(); i++){
encode(baos, tempList.get(i));
}
baos.write('e');
}else if(object instanceof Long){
Long tempLong = (Long)object;
//write out the l
baos.write('i');
write(baos,Constants.DEFAULT_CHARSET.encode(tempLong.toString()));
baos.write('e');
}else if(object instanceof Integer){
Integer tempInteger = (Integer)object;
//write out the l
baos.write('i');
write(baos,Constants.DEFAULT_CHARSET.encode(tempInteger.toString()));
baos.write('e');
}else if(object instanceof byte[]){
byte[] tempByteArray = (byte[])object;
write(baos,Constants.DEFAULT_CHARSET.encode(String.valueOf(tempByteArray.length)));
baos.write(':');
baos.write(tempByteArray);
}else if(object instanceof ByteBuffer ){
ByteBuffer bb = (ByteBuffer)object;
write(baos,Constants.DEFAULT_CHARSET.encode(String.valueOf(bb.limit())));
baos.write(':');
write(baos,bb);
}else if ( object == null ){
// ideally we'd bork here but I don't want to run the risk of breaking existing stuff so just log
Debug.out( "Attempt to encode a null value" );
}else{
Debug.out( "Attempt to encode an unsupported entry type: " + object.getClass() + ";value=" + object);
}
}
protected void
write(
OutputStream os,
ByteBuffer bb )
throws IOException
{
os.write( bb.array(), 0, bb.limit());
}
private static boolean
objectsAreIdentical(
Object o1,
Object o2 )
{
if ( o1 == null && o2 == null ){
return( true );
}else if ( o1 == null || o2 == null ){
return( false );
}
if ( o1 instanceof Integer ){
o1 = new Long(((Integer)o1).longValue());
}
if ( o2 instanceof Integer ){
o2 = new Long(((Integer)o2).longValue());
}
if ( o1 instanceof Float ){
o1 = String.valueOf((Float)o1);
}
if ( o2 instanceof Float ){
o2 = String.valueOf((Float)o2);
}
if ( o1.getClass() != o2.getClass()){
return( false );
}
if ( o1 instanceof Long ){
return( o1.equals( o2 ));
}else if ( o1 instanceof byte[] ){
return( Arrays.equals((byte[])o1,(byte[])o2 ));
}else if ( o1 instanceof ByteBuffer ){
return( o1.equals( o2 ));
}else if ( o1 instanceof String ){
return( o1.equals(o2 ));
}else if ( o1 instanceof List ){
return( listsAreIdentical((List)o1,(List)o2));
}else if ( o1 instanceof Map ){
return( mapsAreIdentical((Map)o1,(Map)o2));
}else{
Debug.out( "Invalid type: " + o1 );
return( false );
}
}
public static boolean
listsAreIdentical(
List list1,
List list2 )
{
if ( list1 == null && list2 == null ){
return( true );
}else if ( list1 == null || list2 == null ){
return( false );
}
if ( list1.size() != list2.size()){
return( false );
}
for ( int i=0;i<list1.size();i++){
if ( !objectsAreIdentical( list1.get(i), list2.get(i))){
return( false );
}
}
return( true );
}
public static boolean
mapsAreIdentical(
Map map1,
Map map2 )
{
if ( map1 == null && map2 == null ){
return( true );
}else if ( map1 == null || map2 == null ){
return( false );
}
if ( map1.size() != map2.size()){
return( false );
}
Iterator it = map1.keySet().iterator();
while( it.hasNext()){
Object key = it.next();
Object v1 = map1.get(key);
Object v2 = map2.get(key);
if ( !objectsAreIdentical( v1, v2 )){
return( false );
}
}
return( true );
}
}
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -