Write a Java program to display all odd numbered files of a text file

import java.io.*; 
public class MyFile { 
BufferedReader in; 
String read; 
int linenum =12;
public MyFile(){ 
try { 
in = new BufferedReader(new FileReader("myfile.txt")); 
for (linenum=0; linenum<20; linenum++){
read = in.readLine();
if(read==null){} 
else{
System.out.println(read);  }
}
in.close(); 
}catch(IOException e){ System.out.println("There was a problem:" + e); 
} 
} 
public static void main(String[] args){ 
MyFile mf = new MyFile(); 
} 
}