Java code for Merge Sort

MergeSort.java

import java.util.*;

public class MergeSort {

	public static void main(String[] args) {
		// get array and call mergeSort() on it
		mergeSort(array);
	}

	public static void mergeSort(int[] array) {
		int n = array.length;
		if (n < 2) // base case, down to one element
			return;
		int mid = n/2;
		int[] left = new int[mid];
		int[] right = new int[n - mid];

		for (int i = 0; i < mid; i++) {
			left[i] = array[i];
		}
		for (int j = mid; j < n; j++) {
			right[j - mid] = array[j];
		}
		mergeSort(left);
		mergeSort(right);
		merge(left, right, array);
	}

	public static void merge(int[] L, int[] R, int[] A) {

		int nL = L.length;
		int nR = R.length;
		int i = 0;
		int j = 0;
		int k = 0;
		while (i < nL && j < nR) {
			if (L[i] <= R[j]) {
				A[k] = L[i];
				i++;
			} else {
				A[k] = R[j];
				j++;
			}
			k++;
		}
		/* Left array isn't empty */
		while (i < nL) {
			A[k] = L[i];
			i++;
			k++;
		}
		/* Right array isn't empty */
		while (j < nR) {
			A[k] = R[j];
			j++;
			k++;
		}
	}
}