### Question:
HMapIS implements MapIS, Cloneable, Serializable { @Override public void increment(int key) { if (this.containsKey(key)) { this.put(key, (short) (this.get(key) + 1)); } else { this.put(key, (short) 1); } } HMapIS(int initialCapacity, float loadFactor);  HMapIS(int initialCapacity);  HMapIS();  HMapIS(MapIS m); @Override int size(); @Override boolean isEmpty(); @Override short get(int key); @Override boolean containsKey(int key); @Override short put(int key, short value); @Override void putAll(MapIS m); @Override short remove(int key); @Override void clear(); @Override boolean containsValue(short value); @Override Object clone(); @Override Set<Integer> keySet(); @Override Collection<Short> values(); @Override Set<MapIS.Entry> entrySet(); @Override String toString(); @Override void plus(MapIS m); @Override long dot(MapIS m); @Override void increment(int key); @Override void increment(int key, short value); MapIS.Entry[] getEntriesSortedByValue(); MapIS.Entry[] getEntriesSortedByValue(int n);  }### Answer:
@Test public void testIncrement() { HMapIS m = new HMapIS(); assertEquals(0, m.get(1)); m.increment(1, (short) 1); assertEquals(1, m.get(1)); m.increment(1); m.increment(2, (short) 0); m.increment(3, (short) -1); assertEquals(2, m.get(1)); assertEquals(0, m.get(2)); assertEquals(-1, m.get(3)); }