CODESAMPLE

Strategy - Java

Strategy Java

The Strategy pattern defines a family of algorithms, encapsulates each one, and makes them interchangeable. It allows an algorithm to vary independently from the clients that use it. This implementation uses a functional interface SortingStrategy to represent different sorting algorithms. The Sorter class accepts a SortingStrategy object in its constructor and delegates the sorting task to it. This promotes loose coupling and allows easily adding new sorting strategies without modifying the Sorter class itself. Java’s lambda expressions make defining the strategies concise and readable, aligning with modern Java practices for functional programming where applicable.

// SortingStrategy.java
@FunctionalInterface
interface SortingStrategy {
    void sort(int[] array);
}

// Sorter.java
class Sorter {
    private final SortingStrategy strategy;

    public Sorter(SortingStrategy strategy) {
        this.strategy = strategy;
    }

    public void performSort(int[] array) {
        strategy.sort(array);
    }
}

// Main.java
public class Main {
    public static void main(String[] args) {
        int[] data = {5, 2, 8, 1, 9, 4};

        // Bubble Sort Strategy
        Sorter bubbleSorter = new Sorter(array -> {
            int n = array.length;
            for (int i = 0; i < n - 1; i++) {
                for (int j = 0; j < n - i - 1; j++) {
                    if (array[j] > array[j + 1]) {
                        // Swap
                        int temp = array[j];
                        array[j] = array[j + 1];
                        array[j + 1] = temp;
                    }
                }
            }
        });

        bubbleSorter.performSort(data.clone()); // Clone to avoid modifying original array
        System.out.println("Bubble Sorted Array: " + java.util.Arrays.toString(data.clone()));


        // Java's built-in Arrays.sort() Strategy
        Sorter javaSorter = new Sorter(array -> java.util.Arrays.sort(array));
        javaSorter.performSort(data.clone());
        System.out.println("Java Sorted Array: " + java.util.Arrays.toString(data.clone()));
    }
}