This code has been deprecated with an alternative version 
at links below:   

NetB project: https://github.com/maoxuli/netb  
DNS examples: https://github.com/maoxuli/netb/tree/master/examples/dns  

Domain Name Service (DNS) is a fundamental part of Internet. 
DNS server stores host addresses of a domain name, as well 
as other kinds of informations. DNS resolver communicates 
with DNS server to retrieve various informations associated 
with a domain.

A DNS resolver is designed and implemented with Object-Oriented 
paradigm. The request and response message of DNS protocol are 
wrapped as Packet object. Resolver send a request message to 
DNS server and the result is returned within a response message. 
Current implementation only parses the resource records with 
types of A, CNAME, and TXT, although other types of resource 
records are also returned within response message. 

The code here is an experimental implementation according to 
RFC 1035 as my class project at the George Washington University. 
There are many issues in design and coding. Please refer to 
abovementioned alternative version.