Merge sort algorithm, Java, with extra memory

package julio;
import java.util.Arrays;

public class Main
{
    public static void main(String[] args) {
    MergeSortExtraMemory sorter = new MergeSortExtraMemory();
    int[] input1 = {10,4,3,5,1,6,6};
   
    int[] m1 = {2};
    int[] m2 = {3};
    System.out.println(Arrays.toString(sorter.merge(m1, m2)));
    System.out.println(Arrays.toString(input1));
    System.out.println(Arrays.toString(sorter.mergeSort(input1)));
    }
}

class MergeSortExtraMemory
{
    public int[] mergeSort(int[] input)
    {
    int size = input.length;
    if( size < 2) {
        return input;
    }
   
    int[] left = new int[size/2];
    int[] right = new int[size/2 + ((size%2==0)? 0 : 1) ];
    for(int i = 0; i < left.length; i++)
        left[i] = input[i];
   
    for(int i = 0 ; i < right.length ; i++)
        right[i] = input[left.length + i];
   
    return merge(mergeSort(left), mergeSort(right));
    }

    public int[] merge(int[] input1, int[] input2)
    {
    int size = input1.length + input2.length;
    int[] out = new int[size];
    int i1 = 0;
    int i2 = 0;
    int outIndex = 0;
    while (i1 < input1.length && i2 < input2.length) {
        if (input1[i1] < input2[i2]){
        out[outIndex++] = input1[i1++];
        } else {
        out[outIndex++] = input2[i2++];
        }
    }
    if (i1 == input1.length) {
        while(i2 < input2.length) {
        out[outIndex++] = input2[i2++];
        }
    } else {
        while(i1 < input1.length) {
        out[outIndex++] = input1[i1++];
        }
    }
    return out;
    }
}