Insertion sort in Java

Insertion sort is an algorithm for sorting an array by iterating through the array and inserting each element into its correct position in a sorted sub-array. It works by maintaining a sorted sub-array at the beginning of the array, and inserting each element into its correct position in the sorted sub-array as it iterates through the array.

Here is an example of how you might implement insertion sort in Java: 

class InsertionSort {

  public static void sort(int[] array) {

    for (int i = 1; i < array.length; i++) {

      int current = array[i];

      int j = i - 1;

      while (j >= 0 && current < array[j]) {

        array[j + 1] = array[j];

        j--;

      }

      array[j + 1] = current;

    }

  }

}

You can then use the sort method to sort an array as follows:

int[] array = {4, 3, 2, 1};

InsertionSort.sort(array);

System.out.println(Arrays.toString(array)); // Outputs [1, 2, 3, 4]