一个不错的加解密代码例子

import   java.io.PrintStream;  
import   java.util.Random;  
 
public class TEST1 {
 public TEST1() {
 }

 public String uCode(String s) {
  int i = s.length();
  String s2 = "";
  if (i == 0)
   return "";
  for (int k = 0; k < i; k++) {
   String s1 = s.substring(k, k + 1);
   int j = s1.hashCode();
   if (j > 255)
    s2 = s2 + String.valueOf((char) (j >> 8))
      + String.valueOf((char) (j & 0xff));
   else
    s2 = s2 + String.valueOf('/0') + s1;
  }

  return s2;
 }

 public String uDCode(String s) {
  int i = s.length();
  if (i % 2 != 0)
   return "-1";
  String s1 = "";
  for (int j = 0; j < i / 2; j++)
   s1 = s1
     + String.valueOf((char) ((s.charAt(j * 2) << 8) + s
       .charAt(j * 2 + 1)));

  return s1;
 }

 public String encodePWS(String s) {
  if (s == null)
   return null;
  int i = s.length();
  if (i == 0)
   return "";
  s = uCode(s);
  i = s.length();
  String s4 = "";
  String s5 = "";
  Random random = new Random();
  boolean flag = false;
  for (int j = 0; j < i; j++) {
   String s1 = Integer
     .toHexString(s.substring(j, j + 1).hashCode() >> 4);
   String s2 = Integer
     .toHexString(s.substring(j, j + 1).hashCode() & 0xf);
   String s3 = Integer.toString(random.nextInt());
   s3 = s3.substring(s3.length() - 1, s3.length());
   if (j % 3 == 0)
    s4 = s4 + s3 + s1 + s2;
   else if (j % 3 == 1)
    s4 = s4 + s1 + s3 + s2;
   else
    s4 = s4 + s1 + s2 + s3;
  }

  return s4;
 }

 public String decodePWS(String s) {
  if (s == null)
   return null;
  int i = s.length();
  if (i == 0)
   return "";
  String s1 = "";
  String s2 = "";
  String s3 = "";
  s2 = s;
  if (s2.length() % 3 != 0)
   return "-1";
  for (int j = 0; j < s2.length() / 3; j++)
   if (j % 3 == 0)
    s1 = s1 + s2.substring(j * 3 + 1, (j + 1) * 3);
   else if (j % 3 == 1)
    s1 = s1 + s2.substring(j * 3, j * 3 + 1)
      + s2.substring(j * 3 + 2, (j + 1) * 3);
   else
    s1 = s1 + s2.substring(j * 3, j * 3 + 2);

  for (int k = 0; k < s1.length() / 2; k++)
   s3 = s3
     + String
       .valueOf((char) ((Char2int(s1.charAt(k * 2)) << 4) + Char2int(s1
         .charAt(k * 2 + 1))));

  s3 = uDCode(s3);
  return s3;
 }

 public int Char2int(char c) {
  if (c >= '0' && c <= '9')
   return c - 48;
  if (c >= 'a' && c <= 'f')
   return (c - 97) + 10;
  else
   return -1;
 }

 public static void main(String args[]) {
  // enCode encode = new enCode();
  TEST1 encode = new TEST1();
  String s = encode
    .encodePWS("字符串加解密测试！ABCD！12345@#$%^&*()<>.,/'");
  System.out.println(s);
  System.out.println("The   encode   lenth   is   " + s.length());
  System.out.println(encode.decodePWS(s));
 }
}