difference between HashMap, Hashset and hashTable?
Answer Posted / adarsh m thimmappa
HashTable is a hashing based key-value pair data structure
- doesn't allow null as key
- doesn't allow null as value as well
- not thread safe
- oldest map based data structure available since earlier versions of java
HashMap is a hashing based key-value pair data structure
- allow one null as key
- allows multiple null as more than one value
- not thread safe
HashSet is a hashing based set representation
- holds unique set of keys
- internally uses HashMap
- allows one null value
- not thread safe
| Is This Answer Correct ? | 0 Yes | 2 No |
Post New Answer View All Answers
What method is invoked to cause an object to begin executing as a separate thread?
Explain about local interfaces.
Can we sent objects using Sockets?
What is the difference between session and entity beans?
Which characters may be used as the second character of an identifier, but not as the first character of an identifier?
How primary key is implemented in Oracle?
which book is better for jdbc ,servlets and jsp
What is the relationship between an event-listener interface and an event-adapter class?
whats is mean by tiles in struts
Explain the different types of memory used by jvm?
In RMI, inorder to sent the stub reference to the client, is we have to load the server object first into the memory or can we directly sent reference to the client?
Explain ioc concept?
Whats new with the stop(), suspend() and resume() methods in jdk 1.2?
Are there books about seam?
What is scalable, portability in the view of J2EE?