### Question:
UpdateRef extends AbstractGeoGigOp<Optional<Ref>> { public UpdateRef setName(String name) { this.name = name; return this; }  UpdateRef setName(String name); UpdateRef setNewValue(ObjectId newValue); UpdateRef setOldValue(ObjectId oldValue); UpdateRef setOldValue(String oldValue); UpdateRef setDelete(boolean delete); UpdateRef setReason(String reason);  }### Answer:
@Test public void testNoValue() { exception.expect(IllegalStateException.class); geogig.command(UpdateRef.class).setName(Ref.MASTER).call(); }