Thursday, December 20, 2001 06:26 AM
There is no HashTree in the standard J2SE 1.3.x distribution.
java.util.HashMap and java.util.Hashtable are mainly the same thing. Both of them implements the java.util.Map interface, and they both are used to map keys to values.
java.util.Hashmap is an 'old' object that has been retrofitted to implement the java.util.Map interface, while java.util.HashMap is one of the addition of the Collection Framework, added starting with J2SE 1.2.
Another difference is in the synchronization. java.util.HashMap is not synchronized, while java.util.Hashtable it is.