Here you can find the source of toHex(byte[] bytes)
| Parameter | Description |
|---|---|
| bytes | array of bytes, least significant at index 0. |
public static String toHex(byte[] bytes)
//package com.java2s; /*/* w w w .j a v a 2s . co m*/ JHeader, a Java library and tools for reading and editing EXIF headers. Copyright (C) 2005 Matthew Baker 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 2 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, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. For further information, please contact Matthew Baker on msb@safe-mail.net. Project home page: www.sourceforge.net/jheader */ public class Main { /** * Converts an array of bytes into a single hex number. * * Always returns two hex digits. * * @param bytes array of bytes, least significant at index 0. * @return uppercase hex string, eg 1F. */ public static String toHex(byte[] bytes) { char[] chars = new char[bytes.length * 2]; for (int i = 0; i < bytes.length; ++i) { int j = i * 2; for (int k = 0; k < 2; ++k) { int byte_i = bytes[i]; if (byte_i < 0) byte_i = 128 - byte_i; int hb = (byte_i >> ((1 - k) * 4)) % 16; switch (hb) { case 0: chars[j + k] = '0'; break; case 1: chars[j + k] = '1'; break; case 2: chars[j + k] = '2'; break; case 3: chars[j + k] = '3'; break; case 4: chars[j + k] = '4'; break; case 5: chars[j + k] = '5'; break; case 6: chars[j + k] = '6'; break; case 7: chars[j + k] = '7'; break; case 8: chars[j + k] = '8'; break; case 9: chars[j + k] = '9'; break; case 10: chars[j + k] = 'A'; break; case 11: chars[j + k] = 'B'; break; case 12: chars[j + k] = 'C'; break; case 13: chars[j + k] = 'D'; break; case 14: chars[j + k] = 'E'; break; case 15: chars[j + k] = 'F'; break; default: ; // can't happen } // switch... } // for (int k... } // for (int i... return new String(chars); } /** * Converts a single unsigned byte into a hex number. * * Always returns two hex digits. * * @param num an unsigned byte to convert, between 0 and 255 inclusive. * @return uppercase hex string, eg 1F. */ public static String toHex(int num) { int ub = (num >> 4) & 0xf; int lb = (num & 0xf); char c1 = ' '; char c2 = ' '; switch (ub) { case 0: c1 = '0'; break; case 1: c1 = '1'; break; case 2: c1 = '2'; break; case 3: c1 = '3'; break; case 4: c1 = '4'; break; case 5: c1 = '5'; break; case 6: c1 = '6'; break; case 7: c1 = '7'; break; case 8: c1 = '8'; break; case 9: c1 = '9'; break; case 10: c1 = 'A'; break; case 11: c1 = 'B'; break; case 12: c1 = 'C'; break; case 13: c1 = 'D'; break; case 14: c1 = 'E'; break; case 15: c1 = 'F'; break; } switch (lb) { case 0: c2 = '0'; break; case 1: c2 = '1'; break; case 2: c2 = '2'; break; case 3: c2 = '3'; break; case 4: c2 = '4'; break; case 5: c2 = '5'; break; case 6: c2 = '6'; break; case 7: c2 = '7'; break; case 8: c2 = '8'; break; case 9: c2 = '9'; break; case 10: c2 = 'A'; break; case 11: c2 = 'B'; break; case 12: c2 = 'C'; break; case 13: c2 = 'D'; break; case 14: c2 = 'E'; break; case 15: c2 = 'F'; break; } return "" + c1 + c2; } /** * Converts an unsigned long value to a hex number. * * Always returns four hex digits. * * @param num an unsigned byte to convert, between 0 and 2^32-1 inclusive. * @return uppercase hex string, eg 001F. */ public static String toHex(long num) { int hint = (int) ((num & 0xff00) >> 8); int lint = (int) (num & 0xff); return toHex(hint) + toHex(lint); } }