Updated

WhosTheBiggest.java

import java.util.Scanner;

public class WhosTheBiggest {

  public static void main(String[] args) {
		Scanner keyboard = new Scanner(System.in);
		while (true) {
			Integer[] inputs = new Integer[3];
			System.out.println("Enter 3 positive digits");
			try {
				inputs[0] = keyboard.nextInt();
				inputs[1] = keyboard.nextInt();
				inputs[2] = keyboard.nextInt();
			} catch (Exception e) {
				System.out.println("Invalid Input: Not an Integer");
				continue;
			}
			
			int maxVal = inputs[0];
			for (int i : inputs) {
				if (!isPositive(i)) {
					System.out.println("Invalid Input: Not a Positive");
					break;
				}
				if (i>maxVal)
					maxVal = i;
			}
			System.out.println("The largest value is: " + maxVal);
			System.out.println("Done");
			System.out.println();
			
		}
	}

	public static boolean isPositive(int input) {
		return input >= 0;
	}
}