java - how to parse only domain name -

i want parse domain name in java. example,

http://facebook.com/bartsf http://www.facebook.com/pages/shine-communications/169790283042195 http://graph.facebook.com/100002306245454/picture?width=150&height=150 http://maps.google.com/maps?hl=en&q=37.78353+-122.39579 http://www.google.com/url?sa=x&q=http://www.onlinehaendler-news.de/interviews/1303-abba24-im-spagat-zwischen-haendler-und-kaeuferinteressen.html&ct=ga&cad=caeqargaiaaoataboafanqsqjwviavaawabiamrl&cd=xa_chwhng70&usg=afqjcnfmgnkzqn0fnkmfkz1ntkk1n9gg9a 

here code writing map reduce code.

 string[] whitelist={"www.facebook.com","www.google.com"};  urlvalidator urlvalidator=new urlvalidator(schemes);  readfile line line  line in file {             string scurrentline=line;             if(scurrentline.length()>=3)             {                 string tempstring=scurrentline.substring(0,3);                  if(!tempstring.equals("192") && !tempstring.equals("172") && !tempstring.equals("10."))                 {                      scurrentline="http://"+scurrentline;                     if(urlvalidator.isvalid(scurrentline))//domain filter should here                     {                            system.out.println(scurrentline);                     }                 }                 tempstring="";             }  } 

i want filter if domain name either facebook.com or google.com urls above filtered out.

use java.net.uri parse strings uris. there's no need reinvent wheel here.

uri foo = new uri("http://facebook.com/bartsf"); string host = foo.gethost(); // "facebook.com"