import java.io.*; public class Main { 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) { String userId = "xiangfei"; //MyEclipse4.1 GA 其中491(4.9.1)/400(4.0)/401(4.1)/501(5.1.0),()内为版本号,9912310代表注册码过期时间2099/12/31 String need = userId.substring(0,1) + "YE3MP-401-00-9912310"; //MyEclipse4.0.0 GA //String need = userId.substring(0,1) + "YE3MP-400-01-9912310"; //MyEclipse4.9.1 //String need = userId.substring(0,1) + "YE3MP-491-01-9912310"; //MyEclipse5.1.0 GA //String need = userId.substring(0,1) + "YE3MP-501-00-9912310"; String dx = need + L + userId; int suf = decode(dx); //System.out.println("SUF:"+suf); String code = need + suf; System.out.println(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) { 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); } }