myEclipseGen.java

 public class MyEclipseGen {
 		private static 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,penalities 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){
 			java.util.Calendar cal =java.util.Calendar.getInstance();
 			cal.add(1,3);
 			cal.add(6,-1);
 			java.text.NumberFormat nf=new java.text.DecimalFormat("000");
 			licenseNum=nf.format(Integer.valueOf(licenseNum));
 			String verTime=new StringBuilder("-").append(new java.text.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(LL).append(userId)
 								.toString();
 			int suf =this.decode(dx);
 			String code=new StringBuilder(need).append(String.valueOf(suf))
 									.toString();
 			return this.change(code);					
 			
 			}
 			private int decode(String s){
 					int i;
 					char[] ac;
 					int j;
 					int k;
 					i=0;
 					ac=s.toCharArray();
 					j=0;
 					k=ac.length;
 					
 					while(j<k){
 							i=(31 * i) + ac[j];
 							j++;
 						}
 						return Math.abs(i);
 						
 				}
 				private String change(String s){
 						byte[] abyte0;
 						char[] ac;
 						int i;
 						int k;
 						int j;
 						abyte0=s.getBytes();
 						ac=new char[s.length()];
 						i=0;
 						k=abyte0.length;
 						while(i<k){
 								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;
 											i++;
 							}
 							return String.valueOf(ac);
 					}
 					public MyEclipseGen(){
 						super();
 						}
 						
 						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("Serial:" + res);
 									reader.readLine();
 								}catch(IOException ex){
 									}
 							}
 	}