web ex13:-

SOURCE CODE:

ECHOSERVLET:

import java.io.*;

import javax.servlet.ServletException;

import javax.servlet.http.*;

public class EchoServlet extends HttpServlet

{

            public void doPost(HttpServletRequest  request,HttpServletResponse response) throws ServletException,IOException

{

            try

            {

                        response.setContentType("application/x-java-serialized-object");

                        InputStream in=request.getInputStream();

                        ObjectInputStream inputFromApplet=new ObjectInputStream(in);

                        String echo=(String)inputFromApplet.readObject();

                        OutputStream outstr=response.getOutputStream();

                        ObjectOutputStream oos=new ObjectOutputStream(outstr);

                        oos.writeObject(echo);

                        oos.flush();

                        oos.close();

            }

            catch(Exception e)

            {

                        e.printStackTrace();

            }

}

}

ECHOAPPLET:

import java.applet.Applet;

import java.awt.*;

import java.awt.event.*;

import java.io.*;

import java.net.*;

public class EchoApplet extends Applet {

private TextField inputField=new TextField();

private TextField outputField=new TextField();

private TextArea exceptionArea=new TextArea();

public void init()

{

            setLayout(new GridBagLayout());

            Label title=new Label("Echo Applet",Label.CENTER);

            title.setFont(new Font("SansSerif",Font.BOLD,14));

            GridBagConstraints c=new GridBagConstraints();

            c.gridwidth=GridBagConstraints.REMAINDER;

            c.weightx=1.0;

            c.fill=GridBagConstraints.HORIZONTAL;

            c.insets=new Insets(5,5,5,5);

            add(title,c);

            c=new GridBagConstraints();

            c.anchor=GridBagConstraints.EAST;

            add(new Label("Input:",Label.RIGHT),c);

            c=new GridBagConstraints();

            c.fill=GridBagConstraints.HORIZONTAL;

            c.weightx=1.0;

            add(inputField,c);

            Button sendButton=new Button("Send");

            c=new GridBagConstraints();

            c.gridwidth=GridBagConstraints.REMAINDER;

            add(sendButton,c);

            sendButton.addActionListener(new ActionListener() {

                        public void actionPerformed(ActionEvent e) {

                                    onSendData();

                        }

            });

            c=new GridBagConstraints();

            c.anchor=GridBagConstraints.EAST;

            add(new Label("Output:",Label.RIGHT),c);

            c=new GridBagConstraints();

            c.gridwidth=GridBagConstraints.REMAINDER;

            c.fill=GridBagConstraints.HORIZONTAL;

            c.weightx=1.0;

            add(outputField,c);

            outputField.setEditable(false);

            c=new GridBagConstraints();

            c.anchor=GridBagConstraints.EAST;

            add(new Label("Exception:",Label.RIGHT),c);

            c=new GridBagConstraints();

            c.gridwidth=GridBagConstraints.REMAINDER;

            c.weighty=1.0;

            c.fill=GridBagConstraints.BOTH;

            add(exceptionArea,c);

            exceptionArea.setEditable(false);                

}

private URLConnection getServletConnection() throws MalformedURLException,IOException

{

            URL urlServlet=new URL("http://localhost:8080/servlet/EchoServlet");

            URLConnection con=urlServlet.openConnection();

            con.setDoInput(true);

            con.setDoOutput(true);

            con.setRequestProperty("Content-Type","application/x-java-serialized-object");

            return con;

}

private void onSendData()

{

            try

            {

                        String input=inputField.getText();

                        URLConnection con=getServletConnection();

                        OutputStream outstream=con.getOutputStream();

                        ObjectOutputStream oos=new ObjectOutputStream(outstream);

                        oos.writeObject(input);

                        oos.flush();

                        oos.close();

           

                        InputStream instr=con.getInputStream();

                        ObjectInputStream inputFromServlet=new ObjectInputStream(instr);

                        String result=(String)inputFromServlet.readObject();

                        inputFromServlet.close();

                        instr.close();

                       

                        outputField.setText(result);

            }

            catch(Exception ex)

            {

                        ex.printStackTrace();

                        exceptionArea.setText(ex.toString());

            }

}

}

<html><applet code="EchoApplet.java" height=600 width=600>

</applet></html>