MapEntry implements Map.Entry<K, V> { public K getKey() { return key; } MapEntry(K key, V value, boolean modifiable); K getKey(); V getValue(); V setValue(V val); @Override @SuppressWarnings("unchecked") boolean equals(Object o); @Override int hashCode();  }
@Test public void testGetKey() { MapEntry<String, String> entry = new MapEntry<String, String>("key", "value", false); assertEquals("key", entry.getKey()); }