### Question:
HMapKL implements MapKL<K>, Cloneable, Serializable { @Override public void increment(K key) { if (this.containsKey(key)) { this.put(key, (long) this.get(key) + 1L); } else { this.put(key, (long) 1L); } } @SuppressWarnings("unchecked")  HMapKL(int initialCapacity, float loadFactor);  HMapKL(int initialCapacity); @SuppressWarnings("unchecked")  HMapKL();  HMapKL(MapKL<? extends K> m); int size(); boolean isEmpty(); long get(K key); boolean containsKey(K key); long put(K key, long value); void putAll(MapKL<? extends K> m); long remove(K key); void clear(); boolean containsValue(long value); @SuppressWarnings("unchecked") Object clone(); Set<K> keySet(); Collection<Long> values(); Set<MapKL.Entry<K>> entrySet(); String toString(); @Override void plus(MapKL<K> m); @Override long dot(MapKL<K> m); @Override void increment(K key); @Override void increment(K key, long value);  }### Answer:
@Test public void testIncrement() { HMapKL<String> m = new HMapKL<String>(); assertEquals(0L, m.get("1")); m.increment("1", 1L); assertEquals(1L, m.get("1")); m.increment("1", 1L); m.increment("2", 0L); m.increment("3", -1L); assertEquals(2L, m.get("1")); assertEquals(0L, m.get("2")); assertEquals(-1L, m.get("3")); m.increment("" + Integer.MAX_VALUE, Integer.MAX_VALUE); assertEquals((long) Integer.MAX_VALUE, m.get("" + Integer.MAX_VALUE)); m.increment("" + Integer.MAX_VALUE); assertEquals(1L + Integer.MAX_VALUE, m.get("" + Integer.MAX_VALUE)); }