Record { public boolean isEmpty() { read.lock(); try { return present.isEmpty() && history.isEmpty(); } finally { read.unlock(); } } protected  Record(L locator, @Nullable K key); void append(Revision<L, K, V> revision); int cardinality(); @Override boolean equals(Object obj); long getVersion(); @Override int hashCode(); boolean isEmpty(); boolean isPartial(); @Override String toString();  }
@Test public void testIsEmpty() { L locator = getLocator(); K key = getKey(); V value = getValue(); record = getRecord(locator, key); Assert.assertTrue(record.isEmpty()); record.append(getRevision(locator, key, value)); Assert.assertFalse(record.isEmpty()); record.append(getRevision(locator, key, value)); Assert.assertTrue(record.describe().isEmpty()); Assert.assertFalse(record.isEmpty()); }