### Question:
DocumentReference extends AbstractLocalizedEntityReference { @Override public DocumentReference replaceParent(EntityReference oldParent, EntityReference newParent) { if (newParent == oldParent) { return this; } return new DocumentReference(this, oldParent, newParent); } DocumentReference(EntityReference reference); protected  DocumentReference(EntityReference reference, EntityReference oldReference, EntityReference newReference);  DocumentReference(EntityReference reference, Locale locale);  DocumentReference(String wikiName, String spaceName, String pageName);  DocumentReference(String wikiName, String spaceName, String pageName, Locale locale);  DocumentReference(String wikiName, String spaceName, String pageName, String language);  DocumentReference(String wikiName, List<String> spaceNames, String pageName);  DocumentReference(String wikiName, List<String> spaceNames, String pageName, Locale locale);  DocumentReference(String pageName, SpaceReference parent);  DocumentReference(LocalDocumentReference localDocumentReference, WikiReference wikiReference);  DocumentReference(String pageName, SpaceReference parent, Locale locale); @Unstable  DocumentReference(String pageName, EntityReference parent, Map<String, Serializable> parameters);  DocumentReference(EntityReference reference, EntityReference parent); @Transient WikiReference getWikiReference(); @Transient DocumentReference setWikiReference(WikiReference wikiReference); @Transient SpaceReference getLastSpaceReference(); @Transient List<SpaceReference> getSpaceReferences(); @Override DocumentReference replaceParent(EntityReference oldParent, EntityReference newParent); @Override DocumentReference replaceParent(EntityReference newParent); @Deprecated LocalDocumentReference getLocaleDocumentReference(); LocalDocumentReference getLocalDocumentReference(); @Override String toString(); static final Type TYPE_PROVIDER; }### Answer:
@Test public void testReplaceParent() { DocumentReference reference = new DocumentReference("wiki", "space", "page").replaceParent( new EntityReference("space2", EntityType.SPACE, new EntityReference("wiki2", EntityType.WIKI))); assertEquals(new DocumentReference("wiki2", "space2", "page"), reference); assertSame(reference, reference.replaceParent(reference.getParent())); }