How can I implement extendible hashing in java?

Question

extendible hashing is one of the best hashing method,I want to create program in java, for extenidble hashing. is there any api available for doing that? i dont get the clear algorithm for doing that myself, so if there is no api, .if possible post algoirhtm

Answer 1

Preface: I do not know what is extendible hashing.

Based on what I understood from this wiki(http://en.wikipedia.org/wiki/Extendible_hashing), that it can search using maximum two lookups, you might want to look at the Java implementation of Bernstein DB (sg-cDB). http://cr.yp.to/cdb.html

Answer 2

Here are some links:

• Java example
• Wikipedia entry
• PPT with some info and an example

Answer 3

this link shows algorithm for Extensible hashing in java and also some program also available in this link

http://my.safaribooksonline.com/0-201-36120-5/ch16lev1sec4#X2ludGVybmFsX0ZsYXNoUmVhZGVyP3htbGlkPTAtMjAxLTM2MTIwLTUvNTc5JmltYWdlcGFnZT01Nzk=

This link gives the more information about extensible hashing

http://www.docstoc.com/docs/12930094/Program-2-Extendible-Hashing..........

Answer 4

I'm just curious, why do you need to implement such an algorithm? Are the standard Java Map implementations not performing for you? If you are suffering from an issue of buckets becoming too heavily loaded you may want to take a look at the hashCode() method before opting for non-standard routes. An alternative could also be to look at some of the options provided by GNU Trove.

Finally - a similar algorithm to Extendible is Cuckoo hashing. Some information below:

http://en.wikipedia.org/wiki/Cuckoo_hashing

Source code here:

http://lmonson.com/blog/?page_id=99