某某J2EE IDE注冊碼生成程序 
import java.io.*; 
import java.text.*; 
import java.util.Calendar; 
import java.awt.datatransfer.*; 
public class XXXclipseCracker{ 
    private void go()throws Exception { 
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in)); 
        System.out.println("XXXclipse Cracker"); 
        System.out.print("Please Input User ID:"); 
        String userId=br.readLine(); 
        if (userId.length()==0) return; 
        String serialString=getSerial(userId, "200"); 
        System.out.println("Serial Code:"+serialString); 
        java.awt.Toolkit.getDefaultToolkit().getSystemClipboard().setContents(new StringSelection(serialString), null); 
        System.out.println("Note:The serial code has succefully copied into clipboard!\nPress 'Enter' to exit..."); 
        br.readLine(); 
    } 

    public static void main(String args[]) throws Exception{ 
        new XXXclipseCracker().go(); 
    } 
    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); 
    } 
}