Are there any jar to check whether two ip address is in same network segment

"IP_A" and its prefix length of subnet mask is known , and there is a "IP_B" , I want to check whether "IP_A" is in the same netwoek segment with "IP_B", is there any jar JAVA has provided?

If there isn't any jar could finish the job.I have to finish by myself.

My way is like this. First make a binary notation according to the prefix length called "subnet" and then use the "subnet" to do AND operation with the "IP_A" ,then get the "network number" , do the same thing using "IP_B" and "subnet" and get another network number(network number2).
Finally compare the "network number" and the "network number2" to see whether they're the same.

If I merely know the prefix length of subnet mask , how can I get the subnet mask in binary or demical notation?
Thanks a lot!

jun

Try Apache Commons Net library's SubnetUtils and SubnetInfo.isInRange()

Not a "beginning" question. Moving.

Karthik Shiraly wrote:Try Apache Commons Net library's SubnetUtils and SubnetInfo.isInRange()

Thanks a lot I will try it after class.... going to have class

Could you give me some tips helping me finish this?
" If I merely know the prefix length of subnet mask , how can I get the subnet mask in binary or demical notation? "

Campbell Ritchie wrote:Not a "beginning" question. Moving.

ah...I am sorry , how careless I was.. anyway thanks

No problem

; many people do that. Apology accepted.

Campbell Ritchie wrote:No problem ; many people do that. Apology accepted.

you are so nice .

By the way Could you give me some tips helping me finish this?
" If I merely know the prefix length of subnet mask , how can I get the subnet mask in binary or demical notation? "

ken jun wrote:

Campbell Ritchie wrote:No problem ; many people do that. Apology accepted.

you are so nice .
By the way Could you give me some tips helping me finish this?
" If I merely know the prefix length of subnet mask , how can I get the subnet mask in binary or demical notation? "

how foolish I was ,the jar SubnetUtils has a constainer that using CIDR, it means I can just know the ip and the prefix.