Question

Thanks for taking a look at my question 🙂

I’m making a program to launch the game “Ace of Spades” for me. The only way to play the game right now is to open up the game website in your browser, search for a good server, and then hope it hasn’t become full by the time you click on it. So I figured that making a launcher to organize these servers for me would be a fun and useful project.

However, I’ve run into a weird error that I’m not sure how to fix: “java.io.IOException: Server reutrned HTTP response code: 403 for URL: http://www.ace-spades.com/play/“.

My browser setup will load most websites just fine (including “https://google.com”), but for some reason the Ace of Spades website is turning it down! It’s not a typo, and the website isn’t down or anything (it loads just fine in Google Chrome), so I think it must be refusing access as a safety protocol to avoid DDoS attacks or something of the sort. So, if it works fine in Chrome, I think that getting my browser to emulate Chrome (or some other popular browser) in a certain regard might solve this problem. Or maybe I’m just doing something silly and stupid in my program (I’m a beginner with Java). Can you help me?

Here is my program:

//*****ADD-ONS*****
package browser;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.HyperlinkEvent;
import javax.swing.event.HyperlinkListener;

import java.net.*;
import java.io.*;

//*****PROGRAM*****
public class MainClass{
    //Initialize general variables
    private JFrame frame;
    private JPanel panelTop;
    private JEditorPane editor;
    private JScrollPane scroll;
    private JTextField field;
    private JButton button;
    private URL url;
    private String windowTitle = "Ace of Spades Launcher";
    private String homePage = "http://www.ace-spades.com/play/"; //"https://google.com";
    private int screenWidth = 854;
    private int screenHeight = 480;

    //MainClass CONSTRUCTOR
    public MainClass(){
        //Initialize Components
        initComponents();

        //Set up frame
        frame.setTitle(windowTitle);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(screenWidth,screenHeight);
        frame.setLocationRelativeTo(null);
        frame.add(BorderLayout.NORTH,panelTop); //Add JPanel to north of JFrame
        panelTop.add(field); //Add TextField to JPanel
        panelTop.add(button); //Add "Go" button to JPanel
        frame.add(BorderLayout.CENTER,scroll); //Add scroll pane to JFrame
        frame.setVisible(true);
    }

    //COMPONENT INITIALIZER
    private void initComponents(){
        frame = new JFrame(); //Create the JFrame
        panelTop = new JPanel(); //Create the JPanel used to hold the text field and button
        try{ //Set the URL
            url = new URL(homePage);
        }catch(MalformedURLException mue){
            JOptionPane.showMessageDialog(null,mue);}
        try{ //Create the JEditorPane
            editor = new JEditorPane(url);
            editor.setEditable(false); //Set the editor pane to false
        }catch(IOException ioe){
            JOptionPane.showMessageDialog(null,ioe);}
        scroll = new JScrollPane( //Create the scroll pane and add the JEditorPane to it
            editor,
            JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
            JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED
        );
        field = new JTextField(); //Create the JTextField
        /**NOTE: We're not doing this on the event dispatch thread, so we need to use SwingUtilities */
        SwingUtilities.invokeLater( //Set the JTextField text to the URL
            new Runnable(){
                public void run(){
                    field.setText(url.toString());
                }
            }
        );
        button = new JButton("Go"); //Create the button for changing pages.
        button.addActionListener( //Add action listener to the button
            new ActionListener(){
                public void actionPerformed(ActionEvent e){
                    try{
                        editor.setPage(field.getText());
                    }catch(IOException ioe){
                        JOptionPane.showMessageDialog(null,ioe);}
                }
            }
        );

        editor.addHyperlinkListener( //Enable hyperlink clicking
            new HyperlinkListener(){
                public void hyperlinkUpdate(HyperlinkEvent e){
                    if (e.getEventType() == HyperlinkEvent.EventType.ACTIVATED){
                        try{
                            editor.setPage(e.getURL());
                        }catch(IOException ioe){
                            JOptionPane.showMessageDialog(null,ioe);}
                    }
                }
            }
        );
    }

    //MAIN PROGRAM EXECUTER
    public static void main(String[] args) {
        SwingUtilities.invokeLater(
            new Runnable(){
                public void run(){
                    new MainClass();}
            }
        );
    }
}

Answer 1

You can use an URLConnection and set the User-Agent:

URL server = new URL("http://www.ace-spades.com/play");
URLConnection connection = server.openConnection();
connection.setRequestProperty("User-Agent", "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_6_8) AppleWebKit/534.57.2 (KHTML, like Gecko) Version/5.1.7 Safari/534.57.2");

Basically, you could subclass JEditorPane and override getStream(URL page) to add the User-Agent string.

import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;

import javax.swing.JEditorPane;

public class UserAgentEditorPane extends JEditorPane {

    private static final long serialVersionUID = 1L;

    private String userAgent;

    public UserAgentEditorPane(URL url, String userAgent) throws IOException {
        super(url);
        this.userAgent = userAgent;
    }

    @Override
    protected InputStream getStream(URL page) throws IOException {
        URLConnection conn = page.openConnection();
        conn.setRequestProperty("User-Agent", userAgent);
        setContentType(conn.getContentType());
        return conn.getInputStream();
    }

}