Simple simulation for how trial software program works in java

import java.io.*;

class Welcome
{
 public void print(){
 System.out.println(“Welcome to learn java”);
 }
}
public class filedel
{
 public static void main(String args[]) throws Exception
 {
  String name=”magic1″;
  boolean flag=false;
  String str=”";
  StringBuffer bu=new StringBuffer();
  RandomAccessFile rand = new RandomAccessFile(“filedel.class”,”rw”);
  int i=(int)rand.length();
  rand.seek(0);  //Seek to start point of file
  for(int ct = 0; ct < i; ct++){
  byte b = rand.readByte();
  bu.append((char)b);
  if(flag==true)
  {
  rand.seek(rand.getFilePointer()-1);
  char out=(char)b;
  str=out+”";
  if(Integer.parseInt(str)==3)
  {
   rand.close();
   File f=new File(“filedel.class”);
   f.delete();
   break;
  }
  rand.writeByte(b+1);
  break;
  }
  if(bu.indexOf(“magic”)!=-1)
  flag=true;
  

  }
  System.out.println(“your currently running “+str+” time this program”);
  Welcome w=new Welcome();
  w.print();
  rand.close();
 }
}

1) save into filedel.java

2) javac filedel.java

3)

java filedel

java filedel

java filedel

java filedel

run class file more than  3 times. see what happen.