/*
 * This is my own work.
 * Dylan Stuart
 */

/*
 * Java program that provides the requirements described by exercise 4.42
 * in the textbook.
 */

public class dcstuart_hwk1 {

    /**
     * Takes an array of arbitrary type and checks to see if 
     * any items within it satisfy a certain condition.
     *
     * @param <T> Data type of the items checked within the array 
     * @param input an array of an arbitrary type
     * @param c a condition to check the array items for
     * @return true if an item within the array satisfies the condition,
     * otherwise false
     */
    public static <T> boolean contains(T[] input, Check<T> c) {
        for (int i = 0; i < input.length; i++) {
            if (c.ok(input[i]) == true) {
                return true;
            }
        }
        return false;
    }

    /**
     * An interface that is used to specify the second parameter of 
     * the contains method,
     *
     * @param <T> The data type of the item being checked
     */
    static public interface Check<T> {

        boolean ok(T item);
    }

    /**
     * PerfectSquare class checks if Integer objects are perfect 
     * squares.
     */
    static public class PerfectSquare implements Check<Integer> {

        @Override
        public boolean ok(Integer val) {
            double root = Math.sqrt(val);
            return val % root == 0;
        }
    }

    /**
     * Prime class checks if Integer objects are prime numbers.
     */
    static public class Prime implements Check<Integer> {

        @Override
        public boolean ok(Integer val) {
            for (int i = 2; i < val / 2; i++) {
                if (val % i == 0) {
                    return false;
                }
            }
            return true;
        }
    }

    /**
     * Negative class checks if Integer objects are negative numbers.
     */
    static public class Negative implements Check<Integer> {

        @Override
        public boolean ok(Integer val) {
            return val < 0;
        }
    }
    
    /*
     * Main method is used to test the example results described in the book
     */

    public static void main(String[] args) {
        Integer[] input = {100, 37, 49};

        boolean result1 = contains(input, new Prime());
        boolean result2 = contains(input, new PerfectSquare());
        boolean result3 = contains(input, new Negative());
        System.out.println(result1);
        System.out.println(result2);
        System.out.println(result3);
    }
}