Java: Sortable interface with bubbleSort and selectionSort implementations

Last update on October 31 2023 12:44:44 (UTC/GMT +8 hours)

Java Interface: Exercise-7 with Solution

Write a Java program to create an interface Sortable with a method sort() that sorts an array of integers in ascending order. Create two classes BubbleSort and SelectionSort that implement the Sortable interface and provide their own implementations of the sort() method.

Sample Solution:

Java Code:

// Sortable.java

// Declare the Sortable interface
interface Sortable {
    // Declare the abstract method "sort" that classes implementing this interface must provide
    void sort(int[] arr);
}

// BubbleSort.java

// Declare the BubbleSort class, which implements the Sortable interface
class BubbleSort implements Sortable {
    // Implement the "sort" method required by the Sortable interface
    public void sort(int[] arr) {
        // Get the length of the array
        int n = arr.length;
        
        // Outer loop for the number of passes
        for (int i = 0; i < n - 1; i++) {
            // Inner loop for comparisons and swaps
            for (int j = 0; j < n - i - 1; j++) {
                if (arr[j] > arr[j + 1]) {
                    // Swap arr[j] and arr[j+1]
                    int temp = arr[j];
                    arr[j] = arr[j + 1];
                    arr[j + 1] = temp;
                }
            }
        }
    }
}

// SelectionSort.java

// Declare the SelectionSort class, which implements the Sortable interface
class SelectionSort implements Sortable {
    // Implement the "sort" method required by the Sortable interface
    public void sort(int[] arr) {
        // Get the length of the array
        int n = arr.length;
        
        // Outer loop for the current element
        for (int i = 0; i < n - 1; i++) {
            int minIndex = i;
            // Inner loop to find the minimum element in the unsorted part of the array
            for (int j = i + 1; j < n; j++) {
                if (arr[j] < arr[minIndex]) {
                    minIndex = j;
                }
            }
            // Swap arr[i] and arr[minIndex]
            int temp = arr[i];
            arr[i] = arr[minIndex];
            arr[minIndex] = temp;
        }
    }
}

// Main.java

// Declare the Main class
public class Main {
    public static void main(String[] args) {
        // Create an array of integers to be sorted
        int[] arr = {
            4,
            2,
            0,
            3,
            1,
            6,
            8
        };

        // Create an instance of BubbleSort and perform sorting
        Sortable bubbleSort = new BubbleSort();
        bubbleSort.sort(arr);
        System.out.print("Bubble Sort: ");
        printArray(arr);

        // Create an instance of SelectionSort and perform sorting
        Sortable selectionSort = new SelectionSort();
        selectionSort.sort(arr);
        System.out.print("Selection Sort: ");
        printArray(arr);
    }

    // Method to print the elements of an array
    private static void printArray(int[] arr) {
        for (int num : arr) {
            System.out.print(num + " ");
        }
        System.out.println();
    }
}

Sample Output:

Bubble Sort: 0 1 2 3 4 6 8
Selection Sort: 0 1 2 3 4 6 8

Explanation:

In the above exercise –

The "BubbleSort" class and "SelectionSort" class both implement the Sortable interface and provide their own implementations of the sort() method. The "BubbleSort" class uses the bubble sort algorithm, and the SelectionSort class uses the selection sort algorithm.

In the main() method, we create an array of integers and then create instances of the BubbleSort and SelectionSort classes. We call the sort() method on each instance, pass in the array, and then print the sorted array using the printArray() method.

Flowchart of Sortable Java: