Map (ADT)

The Map ADT consists of the methods:

• get(k): if map $M$ has an entry $e=(k,v)$, return $v$; else null.
• put(k,v): if $M$ does not have an entry $(k,v)$ then add it to the map $M$ and return null; otherwise, replace $v$ with the new value and return the old value.
• remove(k): if the map $M$ has entry with key $k$, remove it from $M$ and return associated value otherwise return null.
• size(): return number of entries in $M$
• isEmpty(): test whether $M$ is empty
• entrySet(): return an iterable collection of entries in $M$
• keySet(): return an iterable collection of keys in $M$
• values(): return an iterator of the values in $M$