SkiSchool-ejb/src/java/org/cvut/skischool/core/DigestTools.java

   1 package org.cvut.skischool.core;
   2
   3 import java.io.UnsupportedEncodingException;
   4 import java.security.MessageDigest;
   5 import java.security.NoSuchAlgorithmException;
   6 import java.util.logging.Level;
   7 import java.util.logging.Logger;
   8
   9 /**
  10  *
  11  * @author matej
  12  */
  13 public class DigestTools {
  14
  15     public static String SHA1(String text) {
  16         MessageDigest md = null;
  17         byte[] digestOutput = null;
  18
  19         try {
  20             md = MessageDigest.getInstance("SHA1");
  21             md.update(text.getBytes("utf8"), 0, text.length());
  22
  23             digestOutput = new byte[40];
  24             digestOutput = md.digest();
  25         } catch (UnsupportedEncodingException ex) {
  26             Logger.getLogger(DigestTools.class.getName()).log(Level.SEVERE, null, ex);
  27         } catch (NoSuchAlgorithmException ex) {
  28             Logger.getLogger(DigestTools.class.getName()).log(Level.SEVERE, null, ex);
  29         }
  30
  31         return convertToHex(digestOutput);
  32     }
  33
  34     private static String convertToHex(byte[] data) {
  35         StringBuilder buf = new StringBuilder();
  36
  37         for (int i = 0; i < data.length; i++) {
  38             int halfbyte = (data[i] >>> 4) & 0x0F;
  39             int two_halfs = 0;
  40             do {
  41                 if ((0 <= halfbyte) && (halfbyte <= 9)) {
  42                     buf.append((char) ('0' + halfbyte));
  43                 } else {
  44                     buf.append((char) ('a' + (halfbyte - 10)));
  45                 }
  46                 halfbyte = data[i] & 0x0F;
  47             } while (two_halfs++ < 1);
  48         }
  49
  50         return buf.toString();
  51     }
  52 }