1  import java.io.InputStream;

  2  import java.io.IOException;

  3  import java.io.OutputStream;

  4  import java.io.PrintWriter;

  5  import java.net.HttpURLConnection;

  6  import java.net.URL;

  7  import java.net.URLConnection;

  8  import java.util.Scanner;

  9  

 10  /**

 11     This program demonstrates how to use an URL connection 

 12     to communicate with a web server. Supply the URL on the

 13     command-line, for example

 14      java URLGet http://horstmann.com/index.html

 15  */

 16  public class URLGet

 17  {

 18     public static void main(String[] args) throws IOException

 19     {

 20        // Get command-line arguments

 21  

 22        String urlString;      

 23        if (args.length == 1)

 24           urlString = args[0];

 25        else

 26        {

 27           urlString = "http://horstmann.com/";

 28           System.out.println("Using " + urlString);

 29        }

 30  

 31        // Open connection

 32  

 33        URL u = new URL(urlString);

 34        URLConnection connection = u.openConnection();

 35  

 36        // Check if response code is HTTP_OK (200)

 37       

 38        HttpURLConnection httpConnection 

 39              = (HttpURLConnection) connection;

 40        int code = httpConnection.getResponseCode();

 41        String message = httpConnection.getResponseMessage(); 

 42        System.out.println(code + " " + message);

 43        if (code != HttpURLConnection.HTTP_OK)

 44           return;

 45  

 46        // Read server response

 47  

 48        InputStream instream = connection.getInputStream();

 49        Scanner in = new Scanner(instream);

 50  

 51        while (in.hasNextLine())

 52        {

 53           String input = in.nextLine();

 54           System.out.println(input);

 55        }

 56     }

 57  }