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/* * Copyright 2001-2004 The Apache Software Foundation. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.commons.codec.binary; import org.apache.commons.codec.BinaryDecoder; import org.apache.commons.codec.BinaryEncoder; import org.apache.commons.codec.DecoderException; import org.apache.commons.codec.EncoderException; /** * Translates between byte arrays and strings of "0"s and "1"s. * * <b>TODO:</b> may want to add more bit vector functions like and/or/xor/nand. * <B>TODO:</b> also might be good to generate boolean[] * from byte[] et. cetera. * * @author Apache Software Foundation * @since 1.3 * @version $Id $ * * @deprecated Please use {@link java.net.URL#openConnection} instead. * Please visit <a href="http://android-developers.blogspot.com/2011/09/androids-http-clients.html">this webpage</a> * for further details. */ @Deprecated public 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.apache.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.apache.commons.codec.Encoder#encode(java.lang.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.apache.commons.codec.Decoder#decode(java.lang.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.apache.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.apache.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 byte 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 (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; } /** * 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.apache.commons.codec.BinaryEncoder#encode(byte[]) */ public static byte[] toAsciiBytes(byte[] raw) { if (raw == null || raw.length == 0) { 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.apache.commons.codec.BinaryEncoder#encode(byte[]) */ public static char[] toAsciiChars(byte[] raw) { if (raw == null || raw.length == 0) { 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.apache.commons.codec.BinaryEncoder#encode(byte[]) */ public static String toAsciiString(byte[] raw) { return new String(toAsciiChars(raw)); } }