A hashtable will grow as new key, value pairs are inserted. What you are specifying in the constructor is an initial capacity and a load factor (which specifies how full the HashTable gets before increasing it's capacity). The load factor should never be higher than 1.0 . You probably don't need to use this constructor at all. You could just use:
Hashtable hash = new Hashtable();
I am a little confused as to why
hash.get(new Integer(10))
isn't return null.