assertEquals(70, docList.getContentSize());

        docList.addContentSize(-100);
        assertEquals(-30, docList.getContentSize());
    }

    @Test
    public void test_addProcessingTime_negative() {
        DocList docList = new DocList();

        docList.addProcessingTime(100);
        assertEquals(100, docList.getProcessingTime());

        docList.addProcessingTime(-30);