How to get hostname in http url in Java

I have a need to get hostname in httpd url. So. I made it simple by using pattern and matcher class.

public class Util {

public synchronized static String getHost(String domainURL) {

String host = new String();

Pattern pattern = Pattern.compile("(http://)+(\\w++-?\\w++)|(\\w++).?(\\w++.)++(\\w++)");

Matcher match = pattern.matcher(domainURL);

while (match.find()) {

String dashContained = match.group(2);

if (dashContained != null) {

host = match.group(2);

} else {

host = match.group(3);

}

}

return host;

}
}

public class GettingHostTest {

@Test

public void getHost() {

String url = "http://gmail.google.com"; // fulll domain

String host = MonitorUtil.getHost(url);

Assert.assertEndsWith("gmail", host);

}

@Test

public void getHost1() {

String url = "http://gmail1568h125.svr.google.com"; // sub domain

String host = MonitorUtil.getHost(url);

Assert.assertEndsWith("gmail1568h125", host);

}

@Test

public void getHost2() throws Exception {

String url = "http://alpha-gmail.google.com"; // dash contained domain

String host = MonitorUtil.getHost(url);

Assert.assertEndsWith("alpha-gmail", host);

}

}