Java生成Myeclipse注册码

package com.eclipse.subscriber;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Subscriber {
 private static final String LL = "Decompiling this copyrighted software is " +
   "a violation of both your license agreement and the Digital Millenium " +
   "Copyright Act of 1998 (http://www.loc.gov/copyright/legislation/dmca.pdf)" +
   ". Under section 1204 of the DMCA, penalties range up to a " +
   "$500,000 fine or up to five years imprisonment for a first offense." +
   " Think about it; pay for a license, avoid prosecution, and feel better about yourself.";
     

    public static void main(String[] args) {
     try {
             System.out.println("请输入名称:");
             BufferedReader reader = new BufferedReader(new InputStreamReader(
                     System.in));
             String userId = null;
             userId = reader.readLine();
             Subscriber myeclipsegen = new Subscriber();
             String res = myeclipsegen.getSerial(userId, "20");
             System.out.println("您的序列号是:" + res);
             reader.readLine();
         } catch (IOException ex) {
         }

  }
   
    public String getSerial(String userId, String licenseNum) {
         java.util.Calendar cal = java.util.Calendar.getInstance();
         cal.add(1, 3);
         cal.add(6, -1);
         java.text.NumberFormat nf = new java.text.DecimalFormat("000");
         licenseNum = nf.format(Integer.valueOf(licenseNum));
         String verTime = new StringBuilder("-").append(new java.text.
                 SimpleDateFormat("yyMMdd").format(cal.getTime())).append("0").
                          toString();
         String type = "YE3MP-";
         String need = new StringBuilder(userId.substring(0, 1)).append(type).
                       append("300").append(licenseNum).append(verTime).toString();
         String dx = new StringBuilder(need).append(LL).append(userId).toString();
         int suf = this.decode(dx);
         String code = new StringBuilder(need).append(String.valueOf(suf)).
                       toString();
         return this.change(code);
     }

     private int decode(String s) {
         int i;
         char[] ac;
         int j;
         int k;
         i = 0;
         ac = s.toCharArray();
         j = 0;
         k = ac.length;
         while (j < k) {
             i = (31 * i) + ac[j];
             j++;
         }
         return Math.abs(i);
     }

     private String change(String s) {
         byte[] abyte0;
         char[] ac;
         int i;
         int k;
         int j;
         abyte0 = s.getBytes();
         ac = new char[s.length()];
         i = 0;
         k = abyte0.length;
         while (i < k) {
             j = abyte0[i];
             if ((j >= 48) && (j <= 57)) {
                 j = (((j - 48) + 5) % 10) + 48;
             } else if ((j >= 65) && (j <= 90)) {
                 j = (((j - 65) + 13) % 26) + 65;
             } else if ((j >= 97) && (j <= 122)) {
                 j = (((j - 97) + 13) % 26) + 97;
             }
             ac[i] = (char) j;
             i++;
         }
         return String.valueOf(ac);
     }

     public Subscriber() {
         super();
     }

}