public static char reverseBytes(char ch)

// Java program to demonstrate the
// Character.reverseBytes() when a
  
import java.lang.*;
  
public class gfg {
  
    public static void main(String[] args)
    {
  
        // char whose byte order is to be reversed
        char c1 = '\u4d00';
        char c2 = Character.reverseBytes(c1);
  
        // prints the reversed bytes
        System.out.println("Reversing bytes on " + c1 + " gives " + c2);
    }
}

Reversing bytes on ? gives M

// Java program to demonstrate the
// Character.reverseBytes() when a
// number is passed
  
import java.lang.*;
  
public class gfg {
  
    public static void main(String[] args)
    {
  
        // char whose byte order is to be reversed
        char c1 = '9';
        char c2 = Character.reverseBytes(c1);
  
        // prints the reversed bytes
        System.out.println("Reversing bytes on " + c1 + " gives " + c2);
  
        c1 = '7';
        c2 = Character.reverseBytes(c1);
  
        // prints the reversed bytes
        System.out.println("Reversing bytes on " + c1 + " gives " + c2);
    }
}

Reversing bytes on 9 gives ?
Reversing bytes on 7 gives ?