code: public <S, L> JacksonDBCollection<S, L> getCollection(String n, Class<S> type, Class<L> keyType) {
          return wrap(getDB().getCollection(getName() + "." + n), type, keyType, objectMapper);
      }
docs: Finds a collection that is prefixed with this collection's name.
  A typical use of this might be
  <blockquote><pre>
  DBCollection users = mongo.getCollection( "wiki" ).getCollection( "users" );
  </pre></blockquote>
  Which is equivalent to
  <pre><blockquote>
  DBCollection users = mongo.getCollection( "wiki.users" );
  </pre></blockquote>
  
  @param n    the name of the collection to find
  @param type The type of the collection
  @return the matching collection