Web Browser Write a very simple GUI web browser. Your program should have a text

Question

Web Browser

Write a very simple GUI web browser. Your program should have a text edit box at the top of the window for the user to type a URL. Provide a listener that activates when the user types something in and presses “Enter”. The HTTP specification is fairly simple. Create a Socket object from the URL’s web address, connecting on port 80 (the default HTTP port). You will probably want to attach a PrintWriter and a BufferedReader to the Socket. Send the following lines of text, ending in both carriage return and newline characters (yes, HTTP follows Windows line-ending conventions, rather than Unix): GET HTTP/1.1 Host: In other words, if the user typed “http://cs.okstate.edu/students.html”, your program should send these three lines to the Socket: GET /students.html HTTP/1.1 Host: cs.okstate.edu Don’t forget to flush your output afterwards, or your request will never be sent. The web server will respond with a bunch of text including the web page, which you should read into a String. In the program panel, display (as plain text) the body of the webpage (explained below). Make sure that you set up the display so that it includes a scroll bar when needed. You must also handle exceptions and errors gracefully. If the user enters a nonexistent URL, for instance, or if the HTTP response is formatted incorrectly, then the program should inform the user. A proper HTTP response will look like the following: HTTP header junk Several lines User doesn’t want to see this stuff Javascript definitions Other stuff the user doesn’t care about. 2 Here’s all the stuff the user really cares about.

Along with a bunch of formatting,

Explanation / Answer

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.net.*;
import javax.swing.*;
import javax.swing.event.*;

public class WebBrowser extends JFrame implements ActionListener,HyperlinkListener
{
   private JEditorPane pane;
   private JScrollPane spane;
   private Button b1;
   private Button b2;
   private Button b3;
   private TextField addr_bar;
   private URL url;

   public WebBrowser()
   {

       super("WebBrowser");
       setSize(950,700);

       Container c=getContentPane();

       b3=new Button("G0");
       b3.addActionListener(this);

      
       b1=new Button("Close");
       b1.addActionListener(this);

       b2=new Button("Def");
       b2.addActionListener(this);

       addr_bar=new TextField("http://www.");
       addr_bar.addActionListener(this);

       pane=new JEditorPane();
       pane.setEditable(false);
       pane.addHyperlinkListener(this);

      
       c.setLayout(null);

       spane=new JScrollPane(pane);

       spane.setBounds(10,50,940,650);
       addr_bar.setBounds(10,20,740,25);
       b3.setBounds(751,20,50,25);
       b1.setBounds(803,20,50,25);
       b2.setBounds(855,20,50,25);

       c.add(b1);
       c.add(spane);
       c.add(b3);
       c.add(b2);
       c.add(addr_bar);
       show();
       }

   public void actionPerformed(ActionEvent e)
   {
       setTitle("My Web Browser");
       setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));

       Object act=e.getSource();
       String str=addr_bar.getText();

       if (act==b3 || act==addr_bar)
       {
           try {
               pane.setPage(str);
               setTitle("My Web Browser");

           }
           catch (IOException ei)
           {
               try {
               pane.setPage("http://www.jksportshub.com");
               addr_bar.setText("JkSportshub");

               }
               catch (IOException se) {
                   System.out.print("Exception");
               }
           }
       }
       else if (act==b1)
       {
           System.exit(0);
       }

       else if (act=="About")
       {
       JOptionPane.showMessageDialog( this,"Web Brow0.1","Hello ",JOptionPane.INFORMATION_MESSAGE );

       }

      
   }

   public void hyperlinkUpdate( HyperlinkEvent ea )
   {
       if ( ea.getEventType() ==       HyperlinkEvent.EventType.ACTIVATED )
   {
   try {
           pane.setPage( ea.getURL().toString() );
           addr_bar.setText(ea.getURL().toString());
       }
       catch (IOException ei)
       {
               try {
               pane.setPage("http://www.jksportshub.com");
               addr_bar.setText("Default page");
               }
               catch (IOException se) {
                   System.out.print("JKSportsHub");
               }

           }
       }
   }

   public static void main(String[] args)
   {
       WebBrowser web=new WebBrowser();
       web.setVisible(true);
   }

}

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.