Insertion.java

import org.apache.commons.lang3.ArrayUtils;

public class Insertion {
    static void print(Comparable[] a) {
        for (Comparable i : a) System.out.print(i + " ");
        System.out.println();
    }

    static void swap(Comparable [] a, int p, int q) {
        Comparable temp = a[p];
        a[p] = a[q];
        a[q] = temp;
    }

    static boolean less(Comparable a, Comparable b) {
        return a.compareTo(b) < 0;
    }

    public static boolean isSorted(Comparable[] a) {
        for (int i = 1; i < a.length; i++) {
            if (less(a[i], a[i - 1])) return false;
        }
        return true;
    }

    public static void sort(Comparable[] a) {
        for (int i = 1; i < a.length; i++) {
            for (int j = i; j > 0; j--) {
                if (a[j].compareTo(a[j - 1]) < 0){
                    swap(a, j, j - 1);
                    print(a);
                }
                else break;
            }
        }
    }

    public static void main(String[] args) {
        String s = "SHELLSORTEXAMPLE";
        Character[] a= ArrayUtils.toObject(s.toCharArray());
//        Integer[] a = new Integer[]{31, 41, 59, 26, 41, 58};
        print(a);
        sort(a);
        if (!isSorted(a)) throw new AssertionError("Array not sorted");
        print(a);
    }
}