| /* |
| * 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 java.nio.charset.StandardCharsets; |
| |
| import org.apache.commons.codec.BinaryDecoder; |
| import org.apache.commons.codec.BinaryEncoder; |
| import org.apache.commons.codec.CharEncoding; |
| 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 |
| */ |
| public class Hex implements BinaryEncoder, BinaryDecoder { |
| |
| /** |
| * Default charset is {@link StandardCharsets#UTF_8}. |
| * |
| * @since 1.7 |
| */ |
| public static final Charset DEFAULT_CHARSET = StandardCharsets.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 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 of characters or illegal characters are supplied |
| */ |
| public static byte[] decodeHex(final char[] data) throws DecoderException { |
| final byte[] out = new byte[data.length >> 1]; |
| decodeHex(data, out, 0); |
| return out; |
| } |
| |
| /** |
| * 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 |
| * @param out A byte array to contain the binary data decoded from the supplied char array. |
| * @param outOffset The position within {@code out} to start writing the decoded bytes. |
| * @return the number of bytes written to {@code out}. |
| * @throws DecoderException Thrown if an odd number of characters or illegal characters are supplied |
| * @since 1.15 |
| */ |
| public static int decodeHex(final char[] data, final byte[] out, final int outOffset) throws DecoderException { |
| final int len = data.length; |
| |
| if ((len & 0x01) != 0) { |
| throw new DecoderException("Odd number of characters."); |
| } |
| |
| final int outLen = len >> 1; |
| if (out.length - outOffset < outLen) { |
| throw new DecoderException("Output array is not large enough to accommodate decoded data."); |
| } |
| |
| // two characters form the hex value. |
| for (int i = outOffset, 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 outLen; |
| } |
| |
| /** |
| * 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 of characters or illegal characters are supplied |
| * @since 1.11 |
| */ |
| public static byte[] decodeHex(final String data) throws DecoderException { |
| return decodeHex(data.toCharArray()); |
| } |
| |
| /** |
| * 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 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} converts to lowercase, {@code false} 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 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 dataLength = data.length; |
| final char[] out = new char[dataLength << 1]; |
| encodeHex(data, 0, dataLength, toDigits, out, 0); |
| return out; |
| } |
| |
| /** |
| * Converts an array of bytes into an array of characters representing the hexadecimal values of each byte in order. |
| * |
| * @param data a byte[] to convert to hex characters |
| * @param dataOffset the position in {@code data} to start encoding from |
| * @param dataLen the number of bytes from {@code dataOffset} to encode |
| * @param toLowerCase {@code true} converts to lowercase, {@code false} to uppercase |
| * @return A char[] containing the appropriate characters from the alphabet For best results, this should be either |
| * upper- or lower-case hex. |
| * @since 1.15 |
| */ |
| public static char[] encodeHex(final byte[] data, final int dataOffset, final int dataLen, |
| final boolean toLowerCase) { |
| final char[] out = new char[dataLen << 1]; |
| encodeHex(data, dataOffset, dataLen, toLowerCase ? DIGITS_LOWER : DIGITS_UPPER, out, 0); |
| return out; |
| } |
| |
| /** |
| * Converts an array of bytes into an array of characters representing the hexadecimal values of each byte in order. |
| * |
| * @param data a byte[] to convert to hex characters |
| * @param dataOffset the position in {@code data} to start encoding from |
| * @param dataLen the number of bytes from {@code dataOffset} to encode |
| * @param toLowerCase {@code true} converts to lowercase, {@code false} to uppercase |
| * @param out a char[] which will hold the resultant appropriate characters from the alphabet. |
| * @param outOffset the position within {@code out} at which to start writing the encoded characters. |
| * @since 1.15 |
| */ |
| public static void encodeHex(final byte[] data, final int dataOffset, final int dataLen, |
| final boolean toLowerCase, final char[] out, final int outOffset) { |
| encodeHex(data, dataOffset, dataLen, toLowerCase ? DIGITS_LOWER : DIGITS_UPPER, out, outOffset); |
| } |
| |
| /** |
| * Converts an array of bytes into an array of characters representing the hexadecimal values of each byte in order. |
| * |
| * @param data a byte[] to convert to hex characters |
| * @param dataOffset the position in {@code data} to start encoding from |
| * @param dataLen the number of bytes from {@code dataOffset} to encode |
| * @param toDigits the output alphabet (must contain at least 16 chars) |
| * @param out a char[] which will hold the resultant appropriate characters from the alphabet. |
| * @param outOffset the position within {@code out} at which to start writing the encoded characters. |
| */ |
| private static void encodeHex(final byte[] data, final int dataOffset, final int dataLen, final char[] toDigits, |
| final char[] out, final int outOffset) { |
| // two characters form the hex value. |
| for (int i = dataOffset, j = outOffset; i < dataOffset + dataLen; i++) { |
| out[j++] = toDigits[(0xF0 & data[i]) >>> 4]; |
| out[j++] = toDigits[0x0F & data[i]]; |
| } |
| } |
| |
| /** |
| * 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. |
| * |
| * <p>All bytes identified by {@link ByteBuffer#remaining()} will be used; after this method |
| * the value {@link ByteBuffer#remaining() remaining()} will be zero.</p> |
| * |
| * @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 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. |
| * |
| * <p>All bytes identified by {@link ByteBuffer#remaining()} will be used; after this method |
| * the value {@link ByteBuffer#remaining() remaining()} will be zero.</p> |
| * |
| * @param data a byte buffer to convert to hex characters |
| * @param toLowerCase {@code true} converts to lowercase, {@code false} 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 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. |
| * |
| * <p>All bytes identified by {@link ByteBuffer#remaining()} will be used; after this method |
| * the value {@link ByteBuffer#remaining() remaining()} will be zero.</p> |
| * |
| * @param byteBuffer 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 byteBuffer, final char[] toDigits) { |
| return encodeHex(toByteArray(byteBuffer), 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} converts to lowercase, {@code false} to uppercase |
| * @return A String containing lower-case hexadecimal characters |
| * @since 1.11 |
| */ |
| public static String encodeHexString(final byte[] data, final 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. |
| * |
| * <p>All bytes identified by {@link ByteBuffer#remaining()} will be used; after this method |
| * the value {@link ByteBuffer#remaining() remaining()} will be zero.</p> |
| * |
| * @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. |
| * |
| * <p>All bytes identified by {@link ByteBuffer#remaining()} will be used; after this method |
| * the value {@link ByteBuffer#remaining() remaining()} will be zero.</p> |
| * |
| * @param data a byte buffer to convert to hex characters |
| * @param toLowerCase {@code true} converts to lowercase, {@code false} to uppercase |
| * @return A String containing lower-case hexadecimal characters |
| * @since 1.11 |
| */ |
| public static String encodeHexString(final ByteBuffer data, final boolean toLowerCase) { |
| return new String(encodeHex(data, toLowerCase)); |
| } |
| |
| /** |
| * Convert the byte buffer to a byte array. All bytes identified by |
| * {@link ByteBuffer#remaining()} will be used. |
| * |
| * @param byteBuffer the byte buffer |
| * @return the byte[] |
| */ |
| private static byte[] toByteArray(final ByteBuffer byteBuffer) { |
| final int remaining = byteBuffer.remaining(); |
| // Use the underlying buffer if possible |
| if (byteBuffer.hasArray()) { |
| final byte[] byteArray = byteBuffer.array(); |
| if (remaining == byteArray.length) { |
| byteBuffer.position(remaining); |
| return byteArray; |
| } |
| } |
| // Copy the bytes |
| final byte[] byteArray = new byte[remaining]; |
| byteBuffer.get(byteArray); |
| return byteArray; |
| } |
| |
| /** |
| * 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. |
| * |
| * <p>All bytes identified by {@link ByteBuffer#remaining()} will be used; after this method |
| * the value {@link ByteBuffer#remaining() remaining()} will be zero.</p> |
| * |
| * @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(toByteArray(buffer), 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()); |
| } |
| if (object instanceof byte[]) { |
| return decode((byte[]) object); |
| } |
| if (object instanceof ByteBuffer) { |
| return decode((ByteBuffer) object); |
| } |
| 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> |
| * |
| * <p>All bytes identified by {@link ByteBuffer#remaining()} will be used; after this method |
| * the value {@link ByteBuffer#remaining() remaining()} will be zero.</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 { |
| final byte[] byteArray; |
| if (object instanceof String) { |
| byteArray = ((String) object).getBytes(this.getCharset()); |
| } else if (object instanceof ByteBuffer) { |
| byteArray = toByteArray((ByteBuffer) object); |
| } 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 + "]"; |
| } |
| } |