XdsbDocumentReference extends DocumentRequest { @Override public String toString() { StringBuilder builder = new StringBuilder(); builder.append(repositoryUniqueId); builder.append(":"); builder.append(documentUniqueId); return builder.toString(); } XdsbDocumentReference(String documentUniqueId,
			String repositoryUniqueId); @Override String toString(); @Override boolean equals(Object anObject);  }
@Test public void testToString() { assertEquals(REPOSITORY_UNIQUE_ID + ":" + DOCUMENT_UNIQUE_ID, xdsbDocumentReference.toString()); }