| /* Util.java -- Miscellaneous utility methods. |
| Copyright (C) 2004, 2006 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath 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, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package gnu.java.security.x509; |
| |
| import gnu.java.lang.CPStringBuilder; |
| |
| /** |
| * A collection of useful class methods. |
| * |
| * @author Casey Marshall (rsdio@metastatic.org) |
| */ |
| public final class Util |
| { |
| |
| // Constants. |
| // ------------------------------------------------------------------------- |
| |
| public static final String HEX = "0123456789abcdef"; |
| |
| // Class methods. |
| // ------------------------------------------------------------------------- |
| |
| /** |
| * Convert a byte array to a hexadecimal string, as though it were a |
| * big-endian arbitrarily-sized integer. |
| * |
| * @param buf The bytes to format. |
| * @param off The offset to start at. |
| * @param len The number of bytes to format. |
| * @return A hexadecimal representation of the specified bytes. |
| */ |
| public static String toHexString(byte[] buf, int off, int len) |
| { |
| CPStringBuilder str = new CPStringBuilder(); |
| for (int i = 0; i < len; i++) |
| { |
| str.append(HEX.charAt(buf[i+off] >>> 4 & 0x0F)); |
| str.append(HEX.charAt(buf[i+off] & 0x0F)); |
| } |
| return str.toString(); |
| } |
| |
| /** |
| * See {@link #toHexString(byte[],int,int)}. |
| */ |
| public static String toHexString(byte[] buf) |
| { |
| return Util.toHexString(buf, 0, buf.length); |
| } |
| |
| /** |
| * Convert a byte array to a hexadecimal string, separating octets |
| * with the given character. |
| * |
| * @param buf The bytes to format. |
| * @param off The offset to start at. |
| * @param len The number of bytes to format. |
| * @param sep The character to insert between octets. |
| * @return A hexadecimal representation of the specified bytes. |
| */ |
| public static String toHexString(byte[] buf, int off, int len, char sep) |
| { |
| CPStringBuilder str = new CPStringBuilder(); |
| for (int i = 0; i < len; i++) |
| { |
| str.append(HEX.charAt(buf[i+off] >>> 4 & 0x0F)); |
| str.append(HEX.charAt(buf[i+off] & 0x0F)); |
| if (i < len - 1) |
| str.append(sep); |
| } |
| return str.toString(); |
| } |
| |
| /** |
| * See {@link #toHexString(byte[],int,int,char)}. |
| */ |
| public static String toHexString(byte[] buf, char sep) |
| { |
| return Util.toHexString(buf, 0, buf.length, sep); |
| } |
| |
| /** |
| * Create a representation of the given byte array similar to the |
| * output of `hexdump -C', which is |
| * |
| * <p><pre>OFFSET SIXTEEN-BYTES-IN-HEX PRINTABLE-BYTES</pre> |
| * |
| * <p>The printable bytes show up as-is if they are printable and |
| * not a newline character, otherwise showing as '.'. |
| * |
| * @param buf The bytes to format. |
| * @param off The offset to start at. |
| * @param len The number of bytes to encode. |
| * @return The formatted string. |
| */ |
| public static String hexDump(byte[] buf, int off, int len, String prefix) |
| { |
| String nl = System.getProperty("line.separator"); |
| CPStringBuilder str = new CPStringBuilder(); |
| int i = 0; |
| while (i < len) |
| { |
| str.append(prefix); |
| str.append(Util.formatInt(i+off, 16, 8)); |
| str.append(" "); |
| String s = Util.toHexString(buf, i+off, Math.min(16, len-i), ' '); |
| str.append(s); |
| for (int j = 56 - (56 - s.length()); j < 56; j++) |
| str.append(" "); |
| for (int j = 0; j < Math.min(16, len - i); j++) |
| { |
| if ((buf[i+off+j] & 0xFF) < 0x20 || (buf[i+off+j] & 0xFF) > 0x7E) |
| str.append('.'); |
| else |
| str.append((char) (buf[i+off+j] & 0xFF)); |
| } |
| str.append(nl); |
| i += 16; |
| } |
| return str.toString(); |
| } |
| |
| /** |
| * See {@link #hexDump(byte[],int,int,String)}. |
| */ |
| public static String hexDump(byte[] buf, String prefix) |
| { |
| return hexDump(buf, 0, buf.length, prefix); |
| } |
| |
| /** |
| * Format an integer into the specified radix, zero-filled. |
| * |
| * @param i The integer to format. |
| * @param radix The radix to encode to. |
| * @param len The target length of the string. The string is |
| * zero-padded to this length, but may be longer. |
| * @return The formatted integer. |
| */ |
| public static String formatInt(int i, int radix, int len) |
| { |
| String s = Integer.toString(i, radix); |
| CPStringBuilder buf = new CPStringBuilder(); |
| for (int j = 0; j < len - s.length(); j++) |
| buf.append("0"); |
| buf.append(s); |
| return buf.toString(); |
| } |
| |
| /** |
| * Convert a hexadecimal string into its byte representation. |
| * |
| * @param hex The hexadecimal string. |
| * @return The converted bytes. |
| */ |
| public static byte[] toByteArray(String hex) |
| { |
| hex = hex.toLowerCase(); |
| byte[] buf = new byte[hex.length() / 2]; |
| int j = 0; |
| for (int i = 0; i < buf.length; i++) |
| { |
| buf[i] = (byte) ((Character.digit(hex.charAt(j++), 16) << 4) | |
| Character.digit(hex.charAt(j++), 16)); |
| } |
| return buf; |
| } |
| } |