Empties the list associated with the object of all key/value pairs, if there are any.
Returns the current value associated with the given key, or null if the given key does not exist in the list associated with the object.
Returns the name of the nth key in the list, or null if n is greater than or equal to the number of key/value pairs in the object.
Removes the key/value pair with the given key from the list associated with the object, if a key/value pair with the given key exists.
Sets the value of the pair identified by key to value, creating a new key/value pair if none existed for key previously.
Returns the number of key/value pairs currently present in the list associated with the object.