### Question:
HMapKS implements MapKS<K>, Cloneable, Serializable { @Override public void increment(K key) { if (this.containsKey(key)) { this.put(key, (short) (this.get(key) + 1)); } else { this.put(key, (short) 1); } } @SuppressWarnings("unchecked")  HMapKS(int initialCapacity, float loadFactor);  HMapKS(int initialCapacity); @SuppressWarnings("unchecked")  HMapKS();  HMapKS(MapKS<? extends K> m); int size(); boolean isEmpty(); short get(K key); boolean containsKey(K key); short put(K key, short value); void putAll(MapKS<? extends K> m); short remove(K key); void clear(); boolean containsValue(short value); @SuppressWarnings("unchecked") Object clone(); Set<K> keySet(); Collection<Short> values(); Set<MapKS.Entry<K>> entrySet(); String toString(); @Override void plus(MapKS<K> m); @Override long dot(MapKS<K> m); @Override void increment(K key); @Override void increment(K key, short value);  }### Answer:
@Test public void testIncrement() { HMapKS<String> m = new HMapKS<String>(); assertEquals(0, m.get("one")); m.increment("one", (short) 1); assertEquals(1, m.get("one")); m.increment("one", (short) 1); m.increment("two", (short) 0); m.increment("three", (short) -1); assertEquals(2, m.get("one")); assertEquals(0, m.get("two")); assertEquals(-1, m.get("three")); }