Encrypts the string along with salt, Decrypts the string and removes the salt : Encryption « Security « Java

Encrypts the string along with salt, Decrypts the string and removes the salt

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//package org.opentides.util;

import java.io.IOException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Random;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

public class StringUtil {

  private static Random random = new Random((new Date()).getTime());
     * Encrypts the string along with salt 
     * @param userId
     * @return
     * @throws Exception
  public static String encrypt(String userId) {  
    BASE64Encoder encoder = new BASE64Encoder();

    // let's create some dummy salt
    byte[] salt = new byte[8];
    return encoder.encode(salt)+

   * Decrypts the string and removes the salt
   * @param encryptKey
   * @return
   * @throws Exception
  public static String decrypt(String encryptKey) {
    // let's ignore the salt
    if (encryptKey.length() > 12) {
      String cipher = encryptKey.substring(12);
      BASE64Decoder decoder = new BASE64Decoder();
      try {
        return new String(decoder.decodeBuffer(cipher));
      } catch (IOException e) {
      //  throw new InvalidImplementationException(
        //    "Failed to perform decryption for key ["+encryptKey+"]",e);
      return null;



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