myEclipse 注册机类

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.text.DecimalFormat;
import java.text.NumberFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
public class Zhuceji{
private static final String L = "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){
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    String userId = null;
    int intLicenseNum = 1;
    String strLicenseNum = null;
    boolean bProFlag = true;
    String strProFlag = null;
    while ((userId == null) || ("".equals(userId.trim()))) {
      System.out.print("用户名: ");
      try {
        userId = br.readLine();
      }
      catch (IOException ioe1){
      }
    }
    System.out.print("注册码可用的用户数量(默认 1, 最大 999): ");
    try {
      strLicenseNum = br.readLine();
    }
    catch (IOException ioe2)
    {
    }
    Object nf = new DecimalFormat("000");
    if ((strLicenseNum == null) || ("".equals(strLicenseNum.trim())))
      strLicenseNum = ((NumberFormat)nf).format(intLicenseNum);
    else {
      strLicenseNum = ((NumberFormat)nf).format(Integer.parseInt(strLicenseNum));
    }
    System.out.print("个人版 或 标准版(默认 个人版, n 标准版): ");
    try {
      strProFlag = br.readLine();
    }
    catch (IOException ioe3) {
    }
    if ((strProFlag != null) && (!("".equals(strProFlag.trim())))) {
      bProFlag = false;
    }
    Calendar cal = Calendar.getInstance();
    cal.add(1, 2);
    cal.add(6, -1);
    SimpleDateFormat sdf = new SimpleDateFormat("yyMMdd");
    String need = userId.substring(0, 1) + "Y" +
      ((bProFlag) ? "E3MP" : "E2MY") + "-100" + strLicenseNum + "-" +
      sdf.format(cal.getTime()) + "0";
    String dx = need + "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." + userId;
    int suf = decode(dx);
    String code = need + suf;
    System.out.println("注册码: " + change(code));
}
  static int decode(String s) {
    int i = 0;
    char[] ac = s.toCharArray();
    int j = 0;
    for (int k = ac.length; j < k; ++j)
      i = 31 * i + ac[j];
    return Math.abs(i);
  }
  static String change(String s) {
    if ((s == null) || (s.length() == 0))
      return s;
    byte[] abyte0 = s.getBytes();
    char[] ac = new char[s.length()];
    int i = 0;
    for (int k = abyte0.length; i < k; ++i) {
      int 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;
    }
    return String.valueOf(ac);
  }
}