@Test
public void addNullValues() {

    final MultiComparisonNode filterNode = new MultiComparisonNode(
            MultiComparisonNode.Type.IN, "propertyName");
    filterNode.addValue("test1");
    filterNode.addValue(null);
    filterNode.addValue("test2");
    filterNode.addValue(null);
    filterNode.addValue(null);
    filterNode.addValue("test3");
    assertThat(filterNode.getComparisonValue().get(0)).isEqualTo("test1");
    assertThat(filterNode.getComparisonValue().get(1)).isNull();
    assertThat(filterNode.getComparisonValue().get(2)).isEqualTo("test2");
    assertThat(filterNode.getComparisonValue().get(3)).isNull();
    assertThat(filterNode.getComparisonValue().get(4)).isNull();
    assertThat(filterNode.getComparisonValue().get(5)).isEqualTo("test3");
}