Junit测试是否还可以？

Question

The Task is to shift Elements in an array starting with an index equal or bigger than int i, one step to right. Sorry, normally this is easy to google but I have a Junit test which condition I need to meet.

It should meet the requirement of this JUnittest:

@Test
public void testShiftElements() {
    String[] a = { "a", "b", "c", "d", "e" };
    String[] b = a.clone();
    int i = 1;
    Arrays.shiftElements(a, i);
    for (int j = 0; j < i; j++) {
        assertEquals(b[j], a[j]);
    }
    for (int j = i; j < a.length - 1; j++) {
        assertEquals(b[j], a[j + 1]);
    }
}

Does the JUnistest even work, because it seems the test requires that eg "a" should equal "b", "b" should equal "c" . Which is impossible. Here is my code, which shifts.

public static String[] shiftElements(String a[], int i) {

    String[] b = new String[a.length + i];

    for (int j = 0; j < a.length; j++) {
        b[j] = a[j];
    }

    for (int d = i; d < b.length - 1; d++) {
        for (int c = i; c < b.length - 1; c++) {
            String temp = b[c + 1];
            b[c + 1] = b[c];
            b[c] = temp;
        }
    }
    return b;
}

Answer 1

The test was correct had to do it like this. Just without a return, but with void.

public static void shiftElements(String[] a, int i) {
    for (int j = a.length -1; j > i; j--) {
        if (j >= i) {
            a[j] = a[j - i];
        }

    }

}

or like this, if I dont want to delete the last String.

public static void shiftElements(String a[], int i) {
    for (int d = i; d < a.length - 1; d++) {
        for (int c = i; c < a.length - 1; c++) {
            String temp = a[c + 1];
            a[c + 1] = a[c];
            a[c] = temp;
        }
    }
}