What is difference between hash mapping and hash table?

Answers were Sorted based on User's Feedback



What is difference between hash mapping and hash table?..

Answer / khalid

Both provide key-value access to data. The Hashtable is one
of the original collection classes in Java. HashMap is part
of the new Collections Framework, added with Java 2, v1.2.
The key difference between the two is that access to the
Hashtable is synchronized on the table while access to the
HashMap isn't. You can add it, but it isn't there by
default.

Another difference is that iterator in the HashMap is fail-
safe while the enumerator for the Hashtable isn't. If you
change the map while iterating, you'll know.

And, a third difference is that HashMap permits null values
in it, while Hashtable doesn't.

For new code, I would tend to always use HashMap.

Is This Answer Correct ?    11 Yes 1 No

What is difference between hash mapping and hash table?..

Answer / murali.s

hashtable is a Synchronized.
hashmap is not a Synchrobnized.
Hashtable doesn,t accept null key,values
Hashmap accept null key,values

Is This Answer Correct ?    4 Yes 0 No

What is difference between hash mapping and hash table?..

Answer / ravi jain

Khalid's answer is right but it has one mistake i.e.

in second point HashMap is also fail-fast...

Is This Answer Correct ?    1 Yes 0 No

What is difference between hash mapping and hash table?..

Answer / sandya

Yes... I agree with u khalid.
can u send the examples in CFW.
Thanks in Advance.

Is This Answer Correct ?    0 Yes 1 No

What is difference between hash mapping and hash table?..

Answer / khalid

Both provide key-value access to data. The Hashtable is one
of the original collection classes in Java. HashMap is part
of the new Collections Framework, added with Java 2, v1.2.
The key difference between the two is that access to the
Hashtable is synchronized on the table while access to the
HashMap isn't. You can add it, but it isn't there by
default.

Another difference is that iterator in the HashMap is fail-
safe while the enumerator for the Hashtable isn't. If you
change the map while iterating, you'll know.

And, a third difference is that HashMap permits null values
in it, while Hashtable doesn't.

For new code, I would tend to always use HashMap.

Is This Answer Correct ?    0 Yes 5 No

Post New Answer

More Core Java Interview Questions

Why is java called the platform independent programming language?

0 Answers  


What is the unit of plancks constant?

0 Answers  


What is unicode?

1 Answers  


Explain Connection Pooling?

3 Answers  


What is difference between string and new string?

0 Answers  


Which is better ascii or unicode?

0 Answers  


i need to know the website that i can compile and run a java code in online.(while system doesn't contain any jdk and jre)

0 Answers  


How to set the permissions to a file in java?

0 Answers  


What does java se mean?

0 Answers  


what is webservices?

1 Answers   CTS, Ericsson, HCL,


What is the main use of generics in java?

0 Answers  


Explain about object oriented programming and its features?

0 Answers  


Categories