X-Git-Url: https://git.pterodactylus.net/?a=blobdiff_plain;f=src%2Fnet%2Fpterodactylus%2Futil%2Fnumber%2FHex.java;h=de7929e7cfe65e7982a67bd6c9a71055ed80494c;hb=1318ca0dedd3b2c0e5457979b0d4ec111df6fa8d;hp=36cca067a1d5a7b1361b4625dfb08416b95ccf23;hpb=8f3a1fc02cb969beeef635b182c88a68ec3a2d03;p=jSite2.git

diff --git a/src/net/pterodactylus/util/number/Hex.java b/src/net/pterodactylus/util/number/Hex.java
index 36cca06..de7929e 100644
--- a/src/net/pterodactylus/util/number/Hex.java
+++ b/src/net/pterodactylus/util/number/Hex.java
@@ -21,26 +21,68 @@ package net.pterodactylus.util.number;
 
 /**
  * Conversion routines for handling hexadecimal numbers.
- * 
+ *
  * @author David ‘Bombe’ Roden <bombe@freenetproject.org>
- * @version $Id$
  */
 public class Hex {
 
 	/**
 	 * Converts the given byte array to a hexadecimal string.
-	 * 
+	 *
 	 * @param dataBytes
 	 *            The bytes to convert
 	 * @return A string of hexadecimal numbers
 	 */
 	public static String toHex(byte[] dataBytes) {
 		StringBuilder hexString = new StringBuilder(dataBytes.length * 2);
-		for (byte dataByte: dataBytes) {
+		for (byte dataByte : dataBytes) {
 			String hexByte = "0" + Integer.toHexString(dataByte & 0xff);
 			hexString.append(hexByte.substring(hexByte.length() - 2));
 		}
 		return hexString.toString();
 	}
 
+	/**
+	 * Converts the given value to a hexadecimal string and zero-pads it to the
+	 * given number of digits.
+	 *
+	 * @param value
+	 *            The value to convert
+	 * @param digits
+	 *            The number of digits
+	 * @return The formatted hexadecimal value
+	 */
+	public static String toHex(long value, int digits) {
+		StringBuilder hexString = new StringBuilder();
+		hexString.append(Long.toHexString(value));
+		while (hexString.length() < digits) {
+			hexString.insert(0, '0');
+		}
+		return hexString.toString();
+	}
+
+	/**
+	 * Decodes a hexadecimal string into a byte array.
+	 *
+	 * @param hexString
+	 *            The hexadecimal representation to decode
+	 * @return The decoded byte array
+	 * @see Integer#parseInt(java.lang.String, int)
+	 * @throw NumberFormatException if the given string is not the hexadecimal
+	 *        representation of a byte array
+	 */
+	public static byte[] toByte(String hexString) {
+		if ((hexString.length() & 0x01) == 0x01) {
+			/* odd length, this is not correct. */
+			throw new NumberFormatException("hex string must have even length.");
+		}
+		byte[] dataBytes = new byte[hexString.length() / 2];
+		for (int stringIndex = 0; stringIndex < hexString.length(); stringIndex += 2) {
+			String hexNumber = hexString.substring(stringIndex, stringIndex + 2);
+			byte dataByte = (byte) Integer.parseInt(hexNumber, 16);
+			dataBytes[stringIndex / 2] = dataByte;
+		}
+		return dataBytes;
+	}
+
 }