UNIVERSITY AT BUFFALO, THE STATE UNIVERSITY OF NEW YORK
The Department of Computer Science & Engineering

STUART C. SHAPIRO: CSE 115 C

The most useful methods of java.util.HashMap<K,V> are:

• put(K key, V value): Associates the specified value with the specified key in this map.

• get(Object key) : Returns the value to which the specified key is mapped, or null if the map contains no mapping for this key.
  Note: the equals method is used for comparison, not ==.

• remove(Object key) : Removes the mapping for this key from this map if present.

• keySet(): Returns a set of the keys contained in this map.

• values(): Returns a collection of the values contained in this map.

Note that both the set returned by keySet() and the collection returned by values() support for each loops.