Returns {@code true} if this map maps one or more keys to the
specified value. More formally, returns {@code true} if and only if
this map contains at least one mapping to a value {@code v} such
that {@code (value is null ? v is null : value.equals(v))}. This
operation will probably require time linear in the map size for
most implementations.
@param value value whose presence in this map is to be tested
@return {@code true} if a mapping to {@code value} exists;
{@code false} otherwise
Returns {@code true} if this map maps one or more keys to the specified value. More formally, returns {@code true} if and only if this map contains at least one mapping to a value {@code v} such that {@code (value is null ? v is null : value.equals(v))}. This operation will probably require time linear in the map size for most implementations.
@param value value whose presence in this map is to be tested @return {@code true} if a mapping to {@code value} exists; {@code false} otherwise