#vulnerable code 
                                @Test
    public void testArray() {
        JSON json = TestUtils.getJsonAsObject("json");
        JSON.Array array = json.get("array").asArray();

        assertThat(array.size(), is(4));
        assertThat(array.get(0), is(notNullValue()));
        assertThat(array.get(1), is(notNullValue()));
        assertThat(array.get(2), is(notNullValue()));
        assertThat(array.get(3), is(notNullValue()));
    } 
                            #location 6 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                @Test
    public void testArray() {
        JSON json = TestUtils.getJsonAsObject("json");
        JSON.Array array = json.get("array").asArray();

        assertThat(array.size(), is(4));
        assertThat(array.isEmpty(), is(false));
        assertThat(array.get(0), is(notNullValue()));
        assertThat(array.get(1), is(notNullValue()));
        assertThat(array.get(2), is(notNullValue()));
        assertThat(array.get(3), is(notNullValue()));
    }