Answer / deep pratap singh

HashMap HashTable
1> Not Synchronized Synchronized
2> can contain null cann't

You may also make HashMap Synchronized using generic
methods. Using Hashtable is bad habit. Try to avoid it.

Answer / ravikiran

hashmap allows one null key and multiple null values.
hashtable doesn't allow null elements
hashmap is not synchronized
hashtable is snchronized
hashmap is not legacy
hashtable is legacy

Answer / ajay yadav

Hash Map allows null values.
Hash Table dont allows null values.

Answer / javablossom

The Iterator is used in the hashmap is fail-safe and
whereas the Enumerator used in hashtable is not fail-safe.

Answer / sekhar

Both class are under map interface.But hash table is
synchronized.hashMap is not.we can explictly synchronize
hash map by using the method
Collections.synchronizedMap(Hash Map);

Answer / kvn

Hash map contains null values,but hash table does not.

Answer / guest

dfg

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