JUnit Test Case via Private Method in Dijkstra Algorithm

I'm trying to figure out the best way to implement a test case for a class exercise. My class exercise provides the known bug and with this I should write a test case for it to fail, and thus find the bug. It involved using the Dijkstra Algorithm.

This is the correct version of the provided code:

private int getNodeWithMinimumDistanceFromUnsettled()
{
    int min;
    int node = 0;

    Iterator<Integer> iterator = unsettled.iterator();
    node = iterator.next();
    min = distances[node];
    for (int i = 1; i <= number_of_nodes; i++)
    {
        if (unsettled.contains(i))
        {
            if (distances[i] <= min)
            {
                min = distances[i];
                node = i;
            }
        }
    }
    return node;
}

The known bug in a separate version is as follows:

if (unsettled.contains(i))
        {
            if (distances[i] > min)
            {
                min = distances[i];
                node = i;
            }
        }

and here is the JUnit Test case I'm using to find it. I'm trying to access this method with Java Reflection and then try to assert whether the node returned is equal to the node is actually the larger distance.

Here is my test case:

int[][] adjacency = { { 0, 0, 0, 0, 0 },
                          { 0, 0, 9, 10, 0 },
                          { 0, 9, 0, 0, 0 },
                          { 0, 5, 4, 0, 2 },
                          { 0, 5, 4, 3, 0 },
                                             }; 
 Dijkstra d1 = new Dijkstra(4);
 d1.dijkstra_algorithm(adjacency, 1);



    /*
    try {

    nodeMethod =   Dijkstra.class.getDeclaredMethod("getNodeWithMinimumDistanceFromUnsettled");

    } catch (NoSuchMethodException e) {
        System.out.println(e.getMessage());
    }

    nodeMethod.setAccessible(true);

    try {   
            node = (int) nodeMethod.invoke(d1);
            System.out.println("min node is: " + node);     
    } catch (IllegalAccessException | InvocationTargetException e) {
            System.out.println(e.getMessage());
    }

    assertEquals(node, 0); 
    */

When I run the test, it doesn't seem to do anything as I get no output. I feel like I'm overthinking this. Is there an easier way to find this bug without using java reflection?