Does this java homework involve boolean? How to implement the loop?

I am almost a complete beginner.

I need to write a program that asks user to input a binary number, verifies whether the number is in fact binary, and then count the number of 1's in the binary number.

So far I have this:

import java.util.Scanner;
import java.text.DecimalFormat;

public class BinaryWords 
{
    public static void main( String [] args )
    {
    int binaryNumber1;
    int binaryNumber2;
    int binaryNumber3;
    int binaryNumber4;
    int binaryNumber5;
    int binaryNumber6;
    int binaryNumber7;
    int binaryNumber8;
    int binaryNumber9;
    int binaryNumber10;
    int binaryNumberWhole = binaryNumber1 + binaryNumber2 + binaryNumber3
            + binaryNumber4 + binaryNumber5 + binaryNumber6 + binaryNumber7
            + binaryNumber8 + binaryNumber9 + binaryNumber10;

    if 1<binaryNumber1<0

        then final int SENTINEL = binaryNumber1;


    System.out.println( "This program verifies a binary number"
            + "representing a word and then" 
            + "counts how many 1's are in that number");

    System.out.println("Please enter a binary number representing a word");

Not pretty, I know! I am confused as to how to read each binary number in the binary sequence and check for 0 or 1.

Any help would be greatly appreciated!