Java Hashtable class
Java Hashtable class implements a hashtable, which maps keys to values. It inherits Dictionary class and implements the Map interface.
A Hashtable is an array of list. Each list is known as a bucket. The position of bucket is identified by calling the hashcode() method. A Hashtable contains values based on the key.
It contains only unique elements.
It may have not have any null key or value.
Hashtable class declaration
public class Hashtable extends Dictionary implements Map, Cloneable, Serializable