How to normalize a URL in Java?

Question

URL normalization (or URL canonicalization) is the process by which URLs are modified and standardized in a consistent manner. The goal of the normalization p

Answer 1

Have you taken a look at the URI class?

http://docs.oracle.com/javase/7/docs/api/java/net/URI.html#normalize()

Answer 2

In Java, normalize parts of a URL

Example of a URL: https://i0.wp.com:55/lplresearch.com/wp-content/feb.png?ssl=1&myvar=2#myfragment

protocol:        https 
domain name:     i0.wp.com 
subdomain:       i0 
port:            55 
path:            /lplresearch.com/wp-content/uploads/2019/01/feb.png?ssl=1 
query:           ?ssl=1" 
parameters:      &myvar=2 
fragment:        #myfragment 

Code to do the URL parsing:

import java.util.*; 
import java.util.regex.*; 
public class regex { 
    public static String getProtocol(String the_url){ 
        Pattern p = Pattern.compile("^(http|https|smtp|ftp|file|pop)://.*"); 
        Matcher m = p.matcher(the_url); 
        return m.group(1); 
    } 
    public static String getParameters(String the_url){ 
        Pattern p = Pattern.compile(".*(\\?[-a-zA-Z0-9_.@!$&''()*+,;=]+)(#.*)*$");
        Matcher m = p.matcher(the_url); 
        return m.group(1); 
    } 
    public static String getFragment(String the_url){ 
        Pattern p = Pattern.compile(".*(#.*)$"); 
        Matcher m = p.matcher(the_url); 
        return m.group(1); 
    } 
    public static void main(String[] args){ 
        String the_url = 
            "https://i0.wp.com:55/lplresearch.com/" + 
            "wp-content/feb.png?ssl=1&myvar=2#myfragment"; 
        System.out.println(getProtocol(the_url)); 
        System.out.println(getFragment(the_url)); 
        System.out.println(getParameters(the_url)); 
    }   
} 

Prints

https
#myfragment
?ssl=1&myvar=2

You can then push and pull on the parts of the URL until they are up to muster.