How to Extract the Domain Name From a URL in Java

Get Domain Name from Given URL in Java

Do you need to get the domain name from a given URL string? This can be tricky if you do not have the right tools. However, with a little bit of programming knowledge and the correct techniques, you can easily parse a URL and extract the domain name from any given URL string using Java.

Java Libraries For Retrieving Domain Names

Java provides two helpful classes for retrieving domain names: java.net.URI and java.net.URL. Both these classes contain methods which can be used to retrieve the domain name from a given URL string. Here is an example of how to use them:

String url = "http://www.example.com/index.html"; 

// Use java.net.URI 
URI uri = new URI(url); 
String domainName = uri.getHost(); 

// Use java.net.URL 
URL urlClass = new URL(url); 
domainName = urlClass.getHost();

As you can see, the java.net.URI and java.net.URLclasses provide easy access to retrieve the domain name from a given URL string.

Tips for Retrieving Domain Names

When retrieving the domain name from a given URL string, always make sure that the URL is correctly parsed. If the URL string contains whitespaces or other characters, it may be difficult to accurately parse it. Also, make sure that the protocol part of the URL is correctly parsed.

If you are dealing with URLs which contain special characters or non-standard protocols, you may need to write your own parser. You should also take care to properly handle IP addresses and internationalized domain names (which may contain Unicode characters).