Difference between Hash Table and Hash Map?
Answers were Sorted based on User's Feedback
Answer / ranganathkini
Hashtable and HashMap are more less similar to each other
except that the HashMap is unsynchronized and allows nulls
whereas Hashtable is synchronized and does not permit nulls.
Is This Answer Correct ? | 27 Yes | 2 No |
Answer / arun kumar rout
hashtable is Synchronised where as hashmap is not.
Is This Answer Correct ? | 17 Yes | 2 No |
Answer / ravikiran
HashTable is the collection which is legacy.Which doenn't
allows null keys and null values.And methods access is
synchronized.
HashMap is the collection which can allow one null key and
multiple null values.And methods access is not synchronized.
Is This Answer Correct ? | 12 Yes | 2 No |
Answer / guest
Hash Table is synchronized but Hash Map is not. Means Hash
Map allow Null value for key and value but Hash Table does
not allow.
Is This Answer Correct ? | 7 Yes | 5 No |
Answer / guest
HashTable is synchronized where as HashMap is not.
HashMap allows null values for (key,value) for only once
where as HashTable does not.
Is This Answer Correct ? | 2 Yes | 0 No |
Answer / hemasankar reddy suggu
1)Hashtable method all are synchronized where as HashMap
does not Synchornized all methods
2)HAshtable object is thread safe where HashMap object is
not thread Safe
3)Hashtable perfomance is low where Hashtable performance is
High
4)null is not allowed in Hashtable but HAshMap null is allowed
5)Hashtable is Interduced in 1.0V where HashMap interduced
in 1.2V
Is This Answer Correct ? | 1 Yes | 1 No |
Answer / anand
HashTable is the collection which is legacy.Which doenn't
allows null keys and null values.And methods access is
synchronized.
HashMap is the collection which can allow one null key and
multiple null values.And methods access is not synchronized.
Is This Answer Correct ? | 2 Yes | 5 No |
Answer / devendra.m
HashMap and HashTable both are equal...
HashMap is non-synchronized one,where as HashTable
synchronized one.
HashMap allows null as a key & value pair.
where as hashtable wont allows null as key & value pair.
Is This Answer Correct ? | 1 Yes | 6 No |
Answer / santosh nayak
HashMap hm=new HashMap();
hm.put("s","s");
hm.put("a","a");
hm.put(null,"r");
hm.put(null,"t");
hm.put("e","e");
This is the code where we can allow multiple null key values
in HashMap.
Is This Answer Correct ? | 1 Yes | 12 No |
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