| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 java.nio.ByteBuffer; |
| import java.nio.charset.Charset; |
| |
| import org.apache.commons.codec.BinaryDecoder; |
| import org.apache.commons.codec.BinaryEncoder; |
| import org.apache.commons.codec.CharEncoding; |
| import org.apache.commons.codec.Charsets; |
| import org.apache.commons.codec.DecoderException; |
| import org.apache.commons.codec.EncoderException; |
| |
| /** |
| * Converts hexadecimal Strings. The charset used for certain operation can be set, the default is set in |
| * {@link #DEFAULT_CHARSET_NAME} |
| * |
| * This class is thread-safe. |
| * |
| * @since 1.1 |
| * @version $Id$ |
| */ |
| public class Hex implements BinaryEncoder, BinaryDecoder { |
| |
| /** |
| * Default charset is {@link Charsets#UTF_8} |
| * |
| * @since 1.7 |
| */ |
| public static final Charset DEFAULT_CHARSET = Charsets.UTF_8; |
| |
| /** |
| * Default charset name is {@link CharEncoding#UTF_8} |
| * |
| * @since 1.4 |
| */ |
| public static final String DEFAULT_CHARSET_NAME = CharEncoding.UTF_8; |
| |
| /** |
| * Used to build output as Hex |
| */ |
| private static final char[] DIGITS_LOWER = |
| {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'}; |
| |
| /** |
| * Used to build output as Hex |
| */ |
| private static final char[] DIGITS_UPPER = |
| {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'}; |
| |
| /** |
| * Converts a String representing hexadecimal values into an array of bytes of those same values. The |
| * returned array will be half the length of the passed String, as it takes two characters to represent any given |
| * byte. An exception is thrown if the passed String has an odd number of elements. |
| * |
| * @param data |
| * A String containing hexadecimal digits |
| * @return A byte array containing binary data decoded from the supplied char array. |
| * @throws DecoderException |
| * Thrown if an odd number or illegal of characters is supplied |
| * @since 1.11 |
| */ |
| public static byte[] decodeHex(String data) throws DecoderException { |
| return decodeHex(data.toCharArray()); |
| } |
| |
| /** |
| * Converts an array of characters representing hexadecimal values into an array of bytes of those same values. The |
| * returned array will be half the length of the passed array, as it takes two characters to represent any given |
| * byte. An exception is thrown if the passed char array has an odd number of elements. |
| * |
| * @param data |
| * An array of characters containing hexadecimal digits |
| * @return A byte array containing binary data decoded from the supplied char array. |
| * @throws DecoderException |
| * Thrown if an odd number or illegal of characters is supplied |
| */ |
| public static byte[] decodeHex(final char[] data) throws DecoderException { |
| |
| final int len = data.length; |
| |
| if ((len & 0x01) != 0) { |
| throw new DecoderException("Odd number of characters."); |
| } |
| |
| final byte[] out = new byte[len >> 1]; |
| |
| // two characters form the hex value. |
| for (int i = 0, j = 0; j < len; i++) { |
| int f = toDigit(data[j], j) << 4; |
| j++; |
| f = f | toDigit(data[j], j); |
| j++; |
| out[i] = (byte) (f & 0xFF); |
| } |
| |
| return out; |
| } |
| |
| /** |
| * Converts an array of bytes into an array of characters representing the hexadecimal values of each byte in order. |
| * The returned array will be double the length of the passed array, as it takes two characters to represent any |
| * given byte. |
| * |
| * @param data |
| * a byte[] to convert to Hex characters |
| * @return A char[] containing lower-case hexadecimal characters |
| */ |
| public static char[] encodeHex(final byte[] data) { |
| return encodeHex(data, true); |
| } |
| |
| /** |
| * Converts a byte buffer into an array of characters representing the hexadecimal values of each byte in order. |
| * The returned array will be double the length of the passed array, as it takes two characters to represent any |
| * given byte. |
| * |
| * @param data |
| * a byte buffer to convert to Hex characters |
| * @return A char[] containing lower-case hexadecimal characters |
| * @since 1.11 |
| */ |
| public static char[] encodeHex(final ByteBuffer data) { |
| return encodeHex(data, true); |
| } |
| |
| /** |
| * Converts an array of bytes into an array of characters representing the hexadecimal values of each byte in order. |
| * The returned array will be double the length of the passed array, as it takes two characters to represent any |
| * given byte. |
| * |
| * @param data |
| * a byte[] to convert to Hex characters |
| * @param toLowerCase |
| * <code>true</code> converts to lowercase, <code>false</code> to uppercase |
| * @return A char[] containing hexadecimal characters in the selected case |
| * @since 1.4 |
| */ |
| public static char[] encodeHex(final byte[] data, final boolean toLowerCase) { |
| return encodeHex(data, toLowerCase ? DIGITS_LOWER : DIGITS_UPPER); |
| } |
| |
| /** |
| * Converts a byte buffer into an array of characters representing the hexadecimal values of each byte in order. |
| * The returned array will be double the length of the passed array, as it takes two characters to represent any |
| * given byte. |
| * |
| * @param data |
| * a byte buffer to convert to Hex characters |
| * @param toLowerCase |
| * <code>true</code> converts to lowercase, <code>false</code> to uppercase |
| * @return A char[] containing hexadecimal characters in the selected case |
| * @since 1.11 |
| */ |
| public static char[] encodeHex(final ByteBuffer data, final boolean toLowerCase) { |
| return encodeHex(data, toLowerCase ? DIGITS_LOWER : DIGITS_UPPER); |
| } |
| |
| /** |
| * Converts an array of bytes into an array of characters representing the hexadecimal values of each byte in order. |
| * The returned array will be double the length of the passed array, as it takes two characters to represent any |
| * given byte. |
| * |
| * @param data |
| * a byte[] to convert to Hex characters |
| * @param toDigits |
| * the output alphabet (must contain at least 16 chars) |
| * @return A char[] containing the appropriate characters from the alphabet |
| * For best results, this should be either upper- or lower-case hex. |
| * @since 1.4 |
| */ |
| protected static char[] encodeHex(final byte[] data, final char[] toDigits) { |
| final int l = data.length; |
| final char[] out = new char[l << 1]; |
| // two characters form the hex value. |
| for (int i = 0, j = 0; i < l; i++) { |
| out[j++] = toDigits[(0xF0 & data[i]) >>> 4]; |
| out[j++] = toDigits[0x0F & data[i]]; |
| } |
| return out; |
| } |
| |
| /** |
| * Converts a byte buffer into an array of characters representing the hexadecimal values of each byte in order. |
| * The returned array will be double the length of the passed array, as it takes two characters to represent any |
| * given byte. |
| * |
| * @param data |
| * a byte buffer to convert to Hex characters |
| * @param toDigits |
| * the output alphabet (must be at least 16 characters) |
| * @return A char[] containing the appropriate characters from the alphabet |
| * For best results, this should be either upper- or lower-case hex. |
| * @since 1.11 |
| */ |
| protected static char[] encodeHex(final ByteBuffer data, final char[] toDigits) { |
| return encodeHex(data.array(), toDigits); |
| } |
| |
| /** |
| * Converts an array of bytes into a String representing the hexadecimal values of each byte in order. The returned |
| * String will be double the length of the passed array, as it takes two characters to represent any given byte. |
| * |
| * @param data |
| * a byte[] to convert to Hex characters |
| * @return A String containing lower-case hexadecimal characters |
| * @since 1.4 |
| */ |
| public static String encodeHexString(final byte[] data) { |
| return new String(encodeHex(data)); |
| } |
| |
| /** |
| * Converts an array of bytes into a String representing the hexadecimal values of each byte in order. The returned |
| * String will be double the length of the passed array, as it takes two characters to represent any given byte. |
| * |
| * @param data |
| * a byte[] to convert to Hex characters |
| * @param toLowerCase |
| * <code>true</code> converts to lowercase, <code>false</code> to uppercase |
| * @return A String containing lower-case hexadecimal characters |
| * @since 1.11 |
| */ |
| public static String encodeHexString(final byte[] data, boolean toLowerCase) { |
| return new String(encodeHex(data, toLowerCase)); |
| } |
| |
| /** |
| * Converts a byte buffer into a String representing the hexadecimal values of each byte in order. The returned |
| * String will be double the length of the passed array, as it takes two characters to represent any given byte. |
| * |
| * @param data |
| * a byte buffer to convert to Hex characters |
| * @return A String containing lower-case hexadecimal characters |
| * @since 1.11 |
| */ |
| public static String encodeHexString(final ByteBuffer data) { |
| return new String(encodeHex(data)); |
| } |
| |
| /** |
| * Converts a byte buffer into a String representing the hexadecimal values of each byte in order. The returned |
| * String will be double the length of the passed array, as it takes two characters to represent any given byte. |
| * |
| * @param data |
| * a byte buffer to convert to Hex characters |
| * @param toLowerCase |
| * <code>true</code> converts to lowercase, <code>false</code> to uppercase |
| * @return A String containing lower-case hexadecimal characters |
| * @since 1.11 |
| */ |
| public static String encodeHexString(final ByteBuffer data, boolean toLowerCase) { |
| return new String(encodeHex(data, toLowerCase)); |
| } |
| |
| /** |
| * Converts a hexadecimal character to an integer. |
| * |
| * @param ch |
| * A character to convert to an integer digit |
| * @param index |
| * The index of the character in the source |
| * @return An integer |
| * @throws DecoderException |
| * Thrown if ch is an illegal hex character |
| */ |
| protected static int toDigit(final char ch, final int index) throws DecoderException { |
| final int digit = Character.digit(ch, 16); |
| if (digit == -1) { |
| throw new DecoderException("Illegal hexadecimal character " + ch + " at index " + index); |
| } |
| return digit; |
| } |
| |
| private final Charset charset; |
| |
| /** |
| * Creates a new codec with the default charset name {@link #DEFAULT_CHARSET} |
| */ |
| public Hex() { |
| // use default encoding |
| this.charset = DEFAULT_CHARSET; |
| } |
| |
| /** |
| * Creates a new codec with the given Charset. |
| * |
| * @param charset |
| * the charset. |
| * @since 1.7 |
| */ |
| public Hex(final Charset charset) { |
| this.charset = charset; |
| } |
| |
| /** |
| * Creates a new codec with the given charset name. |
| * |
| * @param charsetName |
| * the charset name. |
| * @throws java.nio.charset.UnsupportedCharsetException |
| * If the named charset is unavailable |
| * @since 1.4 |
| * @since 1.7 throws UnsupportedCharsetException if the named charset is unavailable |
| */ |
| public Hex(final String charsetName) { |
| this(Charset.forName(charsetName)); |
| } |
| |
| /** |
| * Converts an array of character bytes representing hexadecimal values into an array of bytes of those same values. |
| * The returned array will be half the length of the passed array, as it takes two characters to represent any given |
| * byte. An exception is thrown if the passed char array has an odd number of elements. |
| * |
| * @param array |
| * An array of character bytes containing hexadecimal digits |
| * @return A byte array containing binary data decoded from the supplied byte array (representing characters). |
| * @throws DecoderException |
| * Thrown if an odd number of characters is supplied to this function |
| * @see #decodeHex(char[]) |
| */ |
| @Override |
| public byte[] decode(final byte[] array) throws DecoderException { |
| return decodeHex(new String(array, getCharset()).toCharArray()); |
| } |
| |
| /** |
| * Converts a buffer of character bytes representing hexadecimal values into an array of bytes of those same values. |
| * The returned array will be half the length of the passed array, as it takes two characters to represent any given |
| * byte. An exception is thrown if the passed char array has an odd number of elements. |
| * |
| * @param buffer |
| * An array of character bytes containing hexadecimal digits |
| * @return A byte array containing binary data decoded from the supplied byte array (representing characters). |
| * @throws DecoderException |
| * Thrown if an odd number of characters is supplied to this function |
| * @see #decodeHex(char[]) |
| * @since 1.11 |
| */ |
| public byte[] decode(final ByteBuffer buffer) throws DecoderException { |
| return decodeHex(new String(buffer.array(), getCharset()).toCharArray()); |
| } |
| |
| /** |
| * Converts a String or an array of character bytes representing hexadecimal values into an array of bytes of those |
| * same values. The returned array will be half the length of the passed String or array, as it takes two characters |
| * to represent any given byte. An exception is thrown if the passed char array has an odd number of elements. |
| * |
| * @param object |
| * A String, ByteBuffer, byte[], or an array of character bytes containing hexadecimal digits |
| * @return A byte array containing binary data decoded from the supplied byte array (representing characters). |
| * @throws DecoderException |
| * Thrown if an odd number of characters is supplied to this function or the object is not a String or |
| * char[] |
| * @see #decodeHex(char[]) |
| */ |
| @Override |
| public Object decode(final Object object) throws DecoderException { |
| if (object instanceof String) { |
| return decode(((String) object).toCharArray()); |
| } else if (object instanceof byte[]) { |
| return decode((byte[]) object); |
| } else if (object instanceof ByteBuffer) { |
| return decode((ByteBuffer) object); |
| } else { |
| try { |
| return decodeHex((char[]) object); |
| } catch (final ClassCastException e) { |
| throw new DecoderException(e.getMessage(), e); |
| } |
| } |
| } |
| |
| /** |
| * Converts an array of bytes into an array of bytes for the characters representing the hexadecimal values of each |
| * byte in order. The returned array will be double the length of the passed array, as it takes two characters to |
| * represent any given byte. |
| * <p> |
| * The conversion from hexadecimal characters to the returned bytes is performed with the charset named by |
| * {@link #getCharset()}. |
| * </p> |
| * |
| * @param array |
| * a byte[] to convert to Hex characters |
| * @return A byte[] containing the bytes of the lower-case hexadecimal characters |
| * @since 1.7 No longer throws IllegalStateException if the charsetName is invalid. |
| * @see #encodeHex(byte[]) |
| */ |
| @Override |
| public byte[] encode(final byte[] array) { |
| return encodeHexString(array).getBytes(this.getCharset()); |
| } |
| |
| /** |
| * Converts byte buffer into an array of bytes for the characters representing the hexadecimal values of each |
| * byte in order. The returned array will be double the length of the passed array, as it takes two characters to |
| * represent any given byte. |
| * <p> |
| * The conversion from hexadecimal characters to the returned bytes is performed with the charset named by |
| * {@link #getCharset()}. |
| * </p> |
| * |
| * @param array |
| * a byte buffer to convert to Hex characters |
| * @return A byte[] containing the bytes of the lower-case hexadecimal characters |
| * @see #encodeHex(byte[]) |
| * @since 1.11 |
| */ |
| public byte[] encode(final ByteBuffer array) { |
| return encodeHexString(array).getBytes(this.getCharset()); |
| } |
| |
| /** |
| * Converts a String or an array of bytes into an array of characters representing the hexadecimal values of each |
| * byte in order. The returned array will be double the length of the passed String or array, as it takes two |
| * characters to represent any given byte. |
| * <p> |
| * The conversion from hexadecimal characters to bytes to be encoded to performed with the charset named by |
| * {@link #getCharset()}. |
| * </p> |
| * |
| * @param object |
| * a String, ByteBuffer, or byte[] to convert to Hex characters |
| * @return A char[] containing lower-case hexadecimal characters |
| * @throws EncoderException |
| * Thrown if the given object is not a String or byte[] |
| * @see #encodeHex(byte[]) |
| */ |
| @Override |
| public Object encode(final Object object) throws EncoderException { |
| byte[] byteArray; |
| if (object instanceof String) { |
| byteArray = ((String) object).getBytes(this.getCharset()); |
| } else if (object instanceof ByteBuffer) { |
| byteArray = ((ByteBuffer) object).array(); |
| } else { |
| try { |
| byteArray = (byte[]) object; |
| } catch (final ClassCastException e) { |
| throw new EncoderException(e.getMessage(), e); |
| } |
| } |
| return encodeHex(byteArray); |
| } |
| |
| /** |
| * Gets the charset. |
| * |
| * @return the charset. |
| * @since 1.7 |
| */ |
| public Charset getCharset() { |
| return this.charset; |
| } |
| |
| /** |
| * Gets the charset name. |
| * |
| * @return the charset name. |
| * @since 1.4 |
| */ |
| public String getCharsetName() { |
| return this.charset.name(); |
| } |
| |
| /** |
| * Returns a string representation of the object, which includes the charset name. |
| * |
| * @return a string representation of the object. |
| */ |
| @Override |
| public String toString() { |
| return super.toString() + "[charsetName=" + this.charset + "]"; |
| } |
| } |