How to Convert from binary to hex in java

SIMPLE ONE LINE CODE TO CONVERT STRING CONTAINING A BINARY VALUE TO HEX

String bin = Integer.toHexString(Integer.parseInt(binOutput, 2));

//when integer size exceeds use Long instead of Integer

String bin = Long .toHexString(Long .parseLong(binOutput, 2));

FULL CODE FOR CONVERSION

import java.io.*;
import java.lang.*;

public class  BinaryToHexadecimal{
  public static void main(String[] args)throws IOException{
  BufferedReader bf= new BufferedReader(new InputStreamReader(System.in));
  System.out.println("Enter the Binary number:");
  String hex = bf.readLine();
  long num = Long.parseLong(hex);
  long rem;
  while(num > 0){
  rem = num % 10;
  num = num / 10;
  if(rem != 0 && rem != 1){
  System.out.println("This is not a binary number.");
  System.out.println("Please try once again.");
  System.exit(0);
  }
  }
  int i= Integer.parseInt(hex,2);
  String hexString = Integer.toHexString(i);
  System.out.println("Hexa decimal: " + hexString);
  }
}

run:
Enter the Binary number:
101010
Hexa decimal: 2a

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