SortArray.java

package com.hawkai;


import java.util.*;

/*
 * Refactor following code to get clean, readable code without coding smells.
 *
 * Hints:
 * There is nothing wrong with this code in terms of functionality.
 * Think of yourself as contributing to the 'clean code' chapter of a
 * book about programming. The code above is the bad example at the beginning.
 * With your refactored example, you should show the reader the difference between
 * code that is working and code that is clean, maintainable and unlikely to introduce bugs
 */
public class SortArray {
    private static final Integer INPUT_SIZE = 5;

    public static void main(String[] args) {
        List<Integer> nums = readInput();
        System.out.printf("Normal List: %s%n", nums);
        /*
         * There is no need to implement our own sorting specially
         * for something as simple as integer.
         *
         * The sort method can be replaced simply by {@link  Collections.sort}
         * since it does check the list size and decide which type
         * of sort is going to be used
         */
        System.out.printf("Sorted List: %s%n", sort(nums));
    }

    /**
     * Read Integer from console into {@link List<Integer>}
     *
     * @return Unsorted {@link List<Integer>}
     */
    private static List<Integer> readInput() {
        Scanner in = new Scanner(System.in);
        List<Integer> nums = new ArrayList<>();
        System.out.printf("Enter %d numbers:%n", INPUT_SIZE);
        while (nums.size() < INPUT_SIZE) {
            append(nums, in);
        }
        return nums;
    }

    /**
     * Append next element in the list in case of non integer input found it will be ignored
     *
     * @param nums list of numbers to append the next input
     * @param in   input scanner to read the next integer from
     */
    private static void append(List<Integer> nums, Scanner in) {
        try {
            nums.add(in.nextInt());
        } catch (NoSuchElementException | IllegalStateException e) {
            System.out.printf("Error while parsing Input %s%n please enter an integer:%n", e.getMessage());
        }
    }

    /**
     * Insertion Sort implementation, not the best option but it works well
     * smaller data sets
     *
     * @param nums @see {@link List<Integer>} input un sorted array
     * @return Sorted @see {@link List<Integer>}
     */
    private static List<Integer> sort(List<Integer> nums) {
        for (int i = 0; i < nums.size(); i++) {
            for (int j = 0; j < nums.size() - 1; j++) {
                if (nums.get(j).compareTo(nums.get(j + 1)) > 0) {
                    Collections.swap(nums, j, j + 1);
                }
            }
        }
        return nums;
    }
}