直接上代码
import java.io.*;import java.text.*;import java.util.Calendar;public class MyEclipseGen{ 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 String getSerial(String userId, String licenseNum) { 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 = (new StringBuilder("-")).append((new 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("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 StringBuilder(need)).append(String.valueOf(suf)).toString(); return change(code); } private 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 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); } public MyEclipseGen() { } public static void main(String args[]) { try { System.out.println("please input register name:"); BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String userId = null; userId = reader.readLine(); MyEclipseGen myeclipsegen = new MyEclipseGen(); String res = myeclipsegen.getSerial(userId, "20"); System.out.println((new StringBuilder()).append("Serial:").append(res).toString()); reader.readLine(); } catch (IOException ex) { } }}