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Awake FILE is a secure Open Source framework that allows to program very easily file uploads/downloads and RPC through http. File transfers include
powerful features like file chunking and automatic recovery mechanism.
Security has been taken into account from the design: server side allows
to specify strong security rules in order to protect the files and to secure the RPC calls.
/*
* This file is part of Awake FILE.
* Awake FILE: Easy file upload & download over HTTP with Java.
* Copyright (C) 2014, KawanSoft SAS
* (http://www.kawansoft.com). All rights reserved.
*
* Awake FILE is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Awake FILE 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301 USA
*
* Any modifications to this file must keep this entire header
* intact.
*/
package org.awakefw.commons.codec.binary;
import org.awakefw.commons.codec.BinaryDecoder;
import org.awakefw.commons.codec.BinaryEncoder;
import org.awakefw.commons.codec.DecoderException;
import org.awakefw.commons.codec.EncoderException;
/**
* Translates between byte arrays and strings of "0"s and "1"s.
*
* TODO: may want to add more bit vector functions like and/or/xor/nand
* TODO: also might be good to generate boolean[] from byte[] et. cetera.
*
* @author Apache Software Foundation
* @since 1.3
* @version $Id: BinaryCodec.java 798433 2009-07-28 07:53:10Z ggregory $
*/
class BinaryCodec implements BinaryDecoder, BinaryEncoder {
/*
* tried to avoid using ArrayUtils to minimize dependencies while using these empty arrays - dep is just not worth
* it.
*/
/** Empty char array. */
private static final char[] EMPTY_CHAR_ARRAY = new char[0];
/** Empty byte array. */
private static final byte[] EMPTY_BYTE_ARRAY = new byte[0];
/** Mask for bit 0 of a byte. */
private static final int BIT_0 = 1;
/** Mask for bit 1 of a byte. */
private static final int BIT_1 = 0x02;
/** Mask for bit 2 of a byte. */
private static final int BIT_2 = 0x04;
/** Mask for bit 3 of a byte. */
private static final int BIT_3 = 0x08;
/** Mask for bit 4 of a byte. */
private static final int BIT_4 = 0x10;
/** Mask for bit 5 of a byte. */
private static final int BIT_5 = 0x20;
/** Mask for bit 6 of a byte. */
private static final int BIT_6 = 0x40;
/** Mask for bit 7 of a byte. */
private static final int BIT_7 = 0x80;
private static final int[] BITS = {BIT_0, BIT_1, BIT_2, BIT_3, BIT_4, BIT_5, BIT_6, BIT_7};
/**
* Converts an array of raw binary data into an array of ASCII 0 and 1 characters.
*
* @param raw
* the raw binary data to convert
* @return 0 and 1 ASCII character bytes one for each bit of the argument
* @see org.awakefw.commons.codec.BinaryEncoder#encode(byte[])
*/
public byte[] encode(byte[] raw) {
return toAsciiBytes(raw);
}
/**
* Converts an array of raw binary data into an array of ASCII 0 and 1 chars.
*
* @param raw
* the raw binary data to convert
* @return 0 and 1 ASCII character chars one for each bit of the argument
* @throws EncoderException
* if the argument is not a byte[]
* @see org.awakefw.commons.codec.Encoder#encode(Object)
*/
public Object encode(Object raw) throws EncoderException {
if (!(raw instanceof byte[])) {
throw new EncoderException("argument not a byte array");
}
return toAsciiChars((byte[]) raw);
}
/**
* Decodes a byte array where each byte represents an ASCII '0' or '1'.
*
* @param ascii
* each byte represents an ASCII '0' or '1'
* @return the raw encoded binary where each bit corresponds to a byte in the byte array argument
* @throws DecoderException
* if argument is not a byte[], char[] or String
* @see org.awakefw.commons.codec.Decoder#decode(Object)
*/
public Object decode(Object ascii) throws DecoderException {
if (ascii == null) {
return EMPTY_BYTE_ARRAY;
}
if (ascii instanceof byte[]) {
return fromAscii((byte[]) ascii);
}
if (ascii instanceof char[]) {
return fromAscii((char[]) ascii);
}
if (ascii instanceof String) {
return fromAscii(((String) ascii).toCharArray());
}
throw new DecoderException("argument not a byte array");
}
/**
* Decodes a byte array where each byte represents an ASCII '0' or '1'.
*
* @param ascii
* each byte represents an ASCII '0' or '1'
* @return the raw encoded binary where each bit corresponds to a byte in the byte array argument
* @see org.awakefw.commons.codec.Decoder#decode(Object)
*/
public byte[] decode(byte[] ascii) {
return fromAscii(ascii);
}
/**
* Decodes a String where each char of the String represents an ASCII '0' or '1'.
*
* @param ascii
* String of '0' and '1' characters
* @return the raw encoded binary where each bit corresponds to a byte in the byte array argument
* @see org.awakefw.commons.codec.Decoder#decode(Object)
*/
public byte[] toByteArray(String ascii) {
if (ascii == null) {
return EMPTY_BYTE_ARRAY;
}
return fromAscii(ascii.toCharArray());
}
// ------------------------------------------------------------------------
//
// static codec operations
//
// ------------------------------------------------------------------------
/**
* Decodes a char array where each char represents an ASCII '0' or '1'.
*
* @param ascii
* each char represents an ASCII '0' or '1'
* @return the raw encoded binary where each bit corresponds to a char in the char array argument
*/
public static byte[] fromAscii(char[] ascii) {
if (ascii == null || ascii.length == 0) {
return EMPTY_BYTE_ARRAY;
}
// get length/8 times bytes with 3 bit shifts to the right of the length
byte[] l_raw = new byte[ascii.length >> 3];
/*
* We decr index jj by 8 as we go along to not recompute indices using multiplication every time inside the
* loop.
*/
for (int ii = 0, jj = ascii.length - 1; ii < l_raw.length; ii++, jj -= 8) {
for (int bits = 0; bits < BITS.length; ++bits) {
if (ascii[jj - bits] == '1') {
l_raw[ii] |= BITS[bits];
}
}
}
return l_raw;
}
/**
* Decodes a byte array where each byte represents an ASCII '0' or '1'.
*
* @param ascii
* each byte represents an ASCII '0' or '1'
* @return the raw encoded binary where each bit corresponds to a byte in the byte array argument
*/
public static byte[] fromAscii(byte[] ascii) {
if (isEmpty(ascii)) {
return EMPTY_BYTE_ARRAY;
}
// get length/8 times bytes with 3 bit shifts to the right of the length
byte[] l_raw = new byte[ascii.length >> 3];
/*
* We decr index jj by 8 as we go along to not recompute indices using multiplication every time inside the
* loop.
*/
for (int ii = 0, jj = ascii.length - 1; ii < l_raw.length; ii++, jj -= 8) {
for (int bits = 0; bits < BITS.length; ++bits) {
if (ascii[jj - bits] == '1') {
l_raw[ii] |= BITS[bits];
}
}
}
return l_raw;
}
/**
* Returns true if the given array is null or empty (size 0.)
*
* @param array
* the source array
* @return true if the given array is null or empty (size 0.)
*/
private static boolean isEmpty(byte[] array) {
return array == null || array.length == 0;
}
/**
* Converts an array of raw binary data into an array of ASCII 0 and 1 character bytes - each byte is a truncated
* char.
*
* @param raw
* the raw binary data to convert
* @return an array of 0 and 1 character bytes for each bit of the argument
* @see org.awakefw.commons.codec.BinaryEncoder#encode(byte[])
*/
public static byte[] toAsciiBytes(byte[] raw) {
if (isEmpty(raw)) {
return EMPTY_BYTE_ARRAY;
}
// get 8 times the bytes with 3 bit shifts to the left of the length
byte[] l_ascii = new byte[raw.length << 3];
/*
* We decr index jj by 8 as we go along to not recompute indices using multiplication every time inside the
* loop.
*/
for (int ii = 0, jj = l_ascii.length - 1; ii < raw.length; ii++, jj -= 8) {
for (int bits = 0; bits < BITS.length; ++bits) {
if ((raw[ii] & BITS[bits]) == 0) {
l_ascii[jj - bits] = '0';
} else {
l_ascii[jj - bits] = '1';
}
}
}
return l_ascii;
}
/**
* Converts an array of raw binary data into an array of ASCII 0 and 1 characters.
*
* @param raw
* the raw binary data to convert
* @return an array of 0 and 1 characters for each bit of the argument
* @see org.awakefw.commons.codec.BinaryEncoder#encode(byte[])
*/
public static char[] toAsciiChars(byte[] raw) {
if (isEmpty(raw)) {
return EMPTY_CHAR_ARRAY;
}
// get 8 times the bytes with 3 bit shifts to the left of the length
char[] l_ascii = new char[raw.length << 3];
/*
* We decr index jj by 8 as we go along to not recompute indices using multiplication every time inside the
* loop.
*/
for (int ii = 0, jj = l_ascii.length - 1; ii < raw.length; ii++, jj -= 8) {
for (int bits = 0; bits < BITS.length; ++bits) {
if ((raw[ii] & BITS[bits]) == 0) {
l_ascii[jj - bits] = '0';
} else {
l_ascii[jj - bits] = '1';
}
}
}
return l_ascii;
}
/**
* Converts an array of raw binary data into a String of ASCII 0 and 1 characters.
*
* @param raw
* the raw binary data to convert
* @return a String of 0 and 1 characters representing the binary data
* @see org.awakefw.commons.codec.BinaryEncoder#encode(byte[])
*/
public static String toAsciiString(byte[] raw) {
return new String(toAsciiChars(raw));
}
}
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