### Question:
AttributeDisplayForm extends DisplayForm implements Updatable { @Override public String toString() { return GoodDataToStringBuilder.defaultToString(this); } @JsonCreator private  AttributeDisplayForm(@JsonProperty("meta") Meta meta, @JsonProperty("content") AttributeContent content,
            @JsonProperty("links") Links links);   AttributeDisplayForm(String title, String formOf, String expression, boolean isDefault, String ldmExpression, String type, String elements); @JsonIgnore boolean isDefault(); @Override String toString();  }### Answer:
@Test public void testToStringFormat() { final DisplayForm attrDF = new AttributeDisplayForm(TITLE, FORM_OF, EXPRESSION, DEFAULT, LDM_EXPRESSION, TYPE, ELEMENTS_LINK); assertThat(attrDF.toString(), matchesPattern(AttributeDisplayForm.class.getSimpleName() + "\\[.*\\]")); }