【JAVA】入力した10進数を2進数で返す

import java.io.*;
public class tentwo{
public static void main(String[]args)throws IOException{
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
String line;
while((line = in.readLine()) != null){
//line = line.toUpperCase();
int i = Integer.parseInt(line);
System.out.println(Integer.toBinaryString(i));
}
}
}