unit test class questions

Maximum Contiguous Subarray Sum (Maximum Subsection Sum)

package com.example.administrator.myapplication;

import java.util.Scanner;

/**
 * Created by Administrator on 2018/4/24.
 */

public class MaxSubArray {
    int maxSum;
    int left;
    int right;

    public int getMaxSubArray1(int[] arr) {
        maxSum = -2147483648 ;
        int sum;
        int len ​​= arr.length;

        for (int i = 0; i <len; i++) {
            sum = 0;
            for (int j = i; j<len; j++) {
                sum += arr[j];
                if (sum > maxSum) {
                    maxSum = sum;
                    left = i;
                    right = j;

                }
            }
        }
        return maxSum;
    }
}

test

package com.example.administrator.myapplication;

import org.junit.Before;
import org.junit.Test;

import static org.junit.Assert.*;

/**
 * Created by Administrator on 2018/4/24.
 */
public class MaxSubArrayTest {
    private  MaxSubArray maxSubArray;
    int[] MaxSubArray = {-1,2,5,3,-4};
    @Before
    public void setUp() throws Exception {
        maxSubArray =new MaxSubArray();
    }
    @Test
    public void getMaxSubArray1() throws Exception {
        assertEquals(8,maxSubArray.getMaxSubArray1(MaxSubArray),2);

    }


}

Test Results