Java URL

The Java URL class represents an URL. URL is an acronym for Uniform Resource Locator. It points to a resource on the World Wide Web. For example:

https://www.rookienerd.com/java-tutorial

A URL contains many information:

Protocol: In this case, http is the protocol.
Server name or IP Address: In this case, www.rookienerd.com is the server name.
Port Number: It is an optional attribute. If we write http//ww.rookienerd.com:80/sonoojaiswal/ , 80 is the port number. If port number is not mentioned in the URL, it returns -1.
File Name or directory name: In this case, index.jsp is the file name.

Constructors of URL class

URL(String spec)

Creates an instance of a URL from the String representation.

URL(String protocol, String host, int port, String file)

Creates an instance of a URL from the given protocol, host, port number, and file.

URL(String protocol, String host, int port, String file, URLStreamHandler handler)

Creates an instance of a URL from the given protocol, host, port number, file, and handler.

URL(String protocol, String host, String file)

Creates an instance of a URL from the given protocol name, host name, and file name.

URL(URL context, String spec)

Creates an instance of a URL by parsing the given spec within a specified context.

URL(URL context, String spec, URLStreamHandler handler)

Creates an instance of a URL by parsing the given spec with the specified handler within a given context.

Commonly used methods of URL class

The java.net.URL class provides many methods. The important methods of URL class are given below.

Method	Description
public String getProtocol()	it returns the protocol of the URL.
public String getHost()	it returns the host name of the URL.
public String getPort()	it returns the Port Number of the URL.
public String getFile()	it returns the file name of the URL.
public String getAuthority()	it returns the authority of the URL.
public String toString()	it returns the string representation of the URL.
public String getQuery()	it returns the query string of the URL.
public String getDefaultPort()	it returns the default port of the URL.
public URLConnection openConnection()	it returns the instance of URLConnection i.e. associated with this URL.
public boolean equals(Object obj)	it compares the URL with the given object.
public Object getContent()	it returns the content of the URL.
public String getRef()	it returns the anchor or reference of the URL.
public URI toURI()	it returns a URI of the URL.

Example #1

snippet

//URLDemo.java
import java.net.*;
public class URLDemo{
public static void main(String[] args){
try{
URL url=new URL("http://www.rookienerd.com/java-tutorial");

System.out.println("Protocol: "+url.getProtocol());
System.out.println("Host Name: "+url.getHost());
System.out.println("Port Number: "+url.getPort());
System.out.println("File Name: "+url.getFile());

}catch(Exception e){System.out.println(e);}
}
}

Output

Protocol: http Host Name: www.rookienerd.com Port Number: -1 File Name: /java-tutorial

Example #2

Let us see another example URL class in Java.

snippet

//URLDemo.java
import java.net.*;  
public class URLDemo{  
public static void main(String[] args){  
try{  
URL url=new URL("https://www.google.com/search?q=rookienerd&oq=rookienerd&sourceid=chrome&ie=UTF-8");  
  
System.out.println("Protocol: "+url.getProtocol());  
System.out.println("Host Name: "+url.getHost());  
System.out.println("Port Number: "+url.getPort());  
System.out.println("Default Port Number: "+url.getDefaultPort());  
System.out.println("Query String: "+url.getQuery());  
System.out.println("Path: "+url.getPath());  
System.out.println("File: "+url.getFile());  

}catch(Exception e){System.out.println(e);}  
}  
}

Output

Protocol: https Host Name: www.google.com Port Number: -1 Default Port Number: 443 Query String: q=rookienerd&oq=rookienerd&sourceid=chrome&ie=UTF-8 Path: /search File: /search?q=rookienerd&oq=rookienerd&sourceid=chrome&ie=UTF-8