Flipping bits

Solution.java

import java.io.*;
import java.util.*;

public class Solution {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int testCases = in.nextInt();
        for (int i=0; i< testCases; i++) {
           if (in.hasNextLong()) {
               long number = in.nextLong();
               //System.out.println("Number: \n" + number);
               String binaryString = Long.toBinaryString(number);
               //System.out.println("Binary String: \n" + binaryString);
               System.out.println(new FlippingBits(binaryString).flip());
           } else {
               throw new RuntimeException(
                   "We have some input problem. [testCases=" + testCases + " i=" + i + "]");
           }
        }
    }
}


class FlippingBits {
    
    private final char[] bits;
    
    public FlippingBits(final String binaryString) {
        this.bits = new char[32];
        Arrays.fill(this.bits, 0, 32, '0');
        char[] binary = binaryString.toCharArray();
        int startPos = 32 - binary.length;
        System.arraycopy(binary, 0, this.bits, startPos, binary.length);
        //System.out.println("Bits: \n" + new String(this.bits));
    }
    
    public Long flip() {
        char[] flipped = new char[32];
        for (int i=0; i < this.bits.length; i++) {
            flipped[i] = this.bits[i] == '0' ? '1' : '0';
        }
        //System.out.println("Flipped: \n" + new String(flipped));
        return Long.valueOf(new String(flipped), 2);
    }
}