diff options
author | Moxie Marlinspike <moxie@thoughtcrime.org> | 2014-11-24 12:54:30 -0800 |
---|---|---|
committer | Moxie Marlinspike <moxie@thoughtcrime.org> | 2014-11-24 12:54:30 -0800 |
commit | 60800e155612bea797eed93c67046a23d26054cc (patch) | |
tree | d88368c1c26162e27e790195133ca2b526597afe /src/main/java/org/whispersystems/libaxolotl/util/Hex.java |
Break out into separate repo.
Diffstat (limited to 'src/main/java/org/whispersystems/libaxolotl/util/Hex.java')
-rw-r--r-- | src/main/java/org/whispersystems/libaxolotl/util/Hex.java | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/src/main/java/org/whispersystems/libaxolotl/util/Hex.java b/src/main/java/org/whispersystems/libaxolotl/util/Hex.java new file mode 100644 index 00000000..19285464 --- /dev/null +++ b/src/main/java/org/whispersystems/libaxolotl/util/Hex.java @@ -0,0 +1,77 @@ +/** + * Copyright (C) 2014 Open Whisper Systems + * + * 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 3 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, see <http://www.gnu.org/licenses/>. + */ +package org.whispersystems.libaxolotl.util; + +import java.io.IOException; + +/** + * Utility for generating hex dumps. + */ +public class Hex { + + private final static char[] HEX_DIGITS = { + '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' + }; + + public static String toString(byte[] bytes) { + return toString(bytes, 0, bytes.length); + } + + public static String toString(byte[] bytes, int offset, int length) { + StringBuffer buf = new StringBuffer(); + for (int i = 0; i < length; i++) { + appendHexChar(buf, bytes[offset + i]); + buf.append(" "); + } + return buf.toString(); + } + + public static String toStringCondensed(byte[] bytes) { + StringBuffer buf = new StringBuffer(); + for (int i=0;i<bytes.length;i++) { + appendHexChar(buf, bytes[i]); + } + return buf.toString(); + } + + public static byte[] fromStringCondensed(String encoded) throws IOException { + final char[] data = encoded.toCharArray(); + final int len = data.length; + + if ((len & 0x01) != 0) { + throw new IOException("Odd number of characters."); + } + + final byte[] out = new byte[len >> 1]; + + for (int i = 0, j = 0; j < len; i++) { + int f = Character.digit(data[j], 16) << 4; + j++; + f = f | Character.digit(data[j], 16); + j++; + out[i] = (byte) (f & 0xFF); + } + + return out; + } + + private static void appendHexChar(StringBuffer buf, int b) { + buf.append(HEX_DIGITS[(b >> 4) & 0xf]); + buf.append(HEX_DIGITS[b & 0xf]); + } + +} |