@Test
public void testToString() {

    ObjectValue ov1 = PropertyValue.createObject("foo");
    String toString = ov1.toString();
    assertThat(toString).isNotNull();
    ov1.addList("list");
    toString = ov1.toString();
    assertThat(toString).isNotNull();
    ov1.addObject("object");
    toString = ov1.toString();
    assertThat(toString).isNotNull();
    ov1.setValue("valueKey", "value");
    toString = ov1.toString();
    assertThat(toString).isNotNull();
    assertThat("Object{size='3', values='{valueKey=value}}").isEqualTo(toString);
}