Returns a {@link Collection} view of the values contained in this map.
The collection is backed by the map, so changes to the map are
reflected in the collection, and vice-versa. If the map is
modified while an iteration over the collection is in progress
(except through the iterator's own <tt>remove</tt> operation),
the results of the iteration are undefined. The collection
supports element removal, which removes the corresponding
mapping from the map, via the <tt>Iterator.remove</tt>,
<tt>Collection.remove</tt>, <tt>removeAll</tt>,
<tt>retainAll</tt> and <tt>clear</tt> operations. It does not
support the <tt>add</tt> or <tt>addAll</tt> operations.
@return a collection view of the values contained in this map
Returns a {@link Collection} view of the values contained in this map. The collection is backed by the map, so changes to the map are reflected in the collection, and vice-versa. If the map is modified while an iteration over the collection is in progress (except through the iterator's own <tt>remove</tt> operation), the results of the iteration are undefined. The collection supports element removal, which removes the corresponding mapping from the map, via the <tt>Iterator.remove</tt>, <tt>Collection.remove</tt>, <tt>removeAll</tt>, <tt>retainAll</tt> and <tt>clear</tt> operations. It does not support the <tt>add</tt> or <tt>addAll</tt> operations.
@return a collection view of the values contained in this map