public class fff {
public static final void main(String[] args){   
 String id="bwrs";   
 String num="999";   
 System.out.println(getSerial(id,"100",num,true));
 }   
 public static String getSerial(String userId, String version,   
 String licenseNum, boolean selected) {   
 Calendar cal = Calendar.getInstance();   
 cal.add(1, 3);   
 cal.add(6, -1);   
 NumberFormat nf = new DecimalFormat("000");   
 licenseNum = nf.format(Integer.valueOf(licenseNum));   
 String verTime = selected ? (new StringBuffer("-")).append(   
 (new SimpleDateFormat("yyMMdd")).format(cal.getTime())).append(   
 "0").toString() : "-0912310";   
 String type = "YE3MB-";   
 String need = (new StringBuffer(String.valueOf(userId.substring(0, 1))))   
 .append(type).append(version).append(licenseNum)   
 .append(verTime).toString();   
 String dx = (new StringBuffer(String.valueOf(need)))   
 .append(   
 "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.")   
   
 .append(userId).toString();   
 int suf = decode(dx);   
 String code = (new StringBuffer(String.valueOf(need))).append(   
 String.valueOf(suf)).toString();   
 return change(code);   
 }   


 private 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);   
 }   


 private static String change(String 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);   
 }   
}