Simple String Encryption

Question

HI,
I have been serching around on here for encyption methods but there seems to be soo many i not sure which ones would be good for me.
All i want to do is encypt and decrypt a String record. The encryption doesnt have to be particulary safe but must work for all possible charaters. Basically i am saving records to a text file and i dont want someone to be able to open the text file and read the contents.
I would like to make it as simple as possible so i can just use it like:
String record = "This is the record";
// Encrypted Record
String encRecord = Encryption.encrypt(record);
// Decripted Record
String decRecord = Encryption.decrypt(record);Can anyone stear me in the right direction or give me some sample code i can study.
Thank you in advance
ed

Answer 1

Here is simple encryption routine that I just wrote that I bet would keep someone
stumped for a while.
* This is a simple encryption class that uses simple character substitution.
* To keep the pattern from being obvious the shift factor is a function of the current character's
* position in the source string. This makes sure that all letters aren't encrypted to the same value.
* Usage: To encrypt a string just pass it to the encrypt method.
*         String encryptedString = Encryptor.encrypt("Some string.");
*        To decrypt a string just pass the encrypted string to the decrypt method.
*         String decryptedString = Encryptor.decrypt(encryptedString);
class Encryptor
  static final byte [] shiftFactor = {2,5,7,9,13,17,19};
  static final int modulo = shiftFactor.length;
  static public String encrypt(String s)
     char [] ba = s.toCharArray();
     for (int i = 0; i < ba.length; i++)
          ba[i] += shiftFactor[i%modulo];
    return new String(ba);
  static public String decrypt(String s)
     char [] ba = s.toCharArray();
     for (int i = 0; i < ba.length; i++)
          ba[i] -= shiftFactor[i%modulo];
     return new String(ba);
  public static void main(String [] args)
     String [] test = {"AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz,./<>?;':\"[]{}-=_+!@#$%^&*()`~",
                       "Now is the time for all good men \n to come to the aid of their country."};
    for (int i = 0; i < test.length; i++)
          System.out.println(test);
          String encrypted = Encryptor.encrypt(test[i]);
          System.out.println(encrypted);
          System.out.println(Encryptor.decrypt(encrypted) + "\n");