Applet To Servlet Communication

Java Example Program / Sample Source Code

import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.net.*;

public class AppletToServletExample extends Applet {
private TextField inputField = new TextField(10);
private TextField resultField = new TextField(10);

public void init() {
    // add input label, field and send button
    add(new Label("Input Your Name", Label.RIGHT));
    add(inputField);
    Button sendButton = new Button("Send");
    add(sendButton);
    sendButton.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        SendData();
      }
    });
    // add output label as a non editable field
    add(new Label("Output:", Label.RIGHT));
    add(resultField);
    resultField.setEditable(false);
}

// Get a connection to the servlet.
private URLConnection getServletConnection() throws MalformedURLException,
      IOException {
    URL urlServlet = new URL(getCodeBase(), "applettoservlet");
    URLConnection con = urlServlet.openConnection();
    con.setDoInput(true);
    con.setDoOutput(true);
    con.setUseCaches(false);
    con.setRequestProperty("Content-Type",
        "application/x-java-serialized-object");
    return con;
}

// Send the inputField data to the servlet and show the result in the
// outputField.
private void SendData() {
    try {
      String input = inputField.getText();
      // send data to the servlet
      URLConnection con = getServletConnection();
      OutputStream outputStream = con.getOutputStream();
      ObjectOutputStream oos = new ObjectOutputStream(outputStream);
      oos.writeObject(input);
      oos.flush();
      oos.close();
      // receive result from servlet
      InputStream inputStream = con.getInputStream();
      ObjectInputStream inputFromServlet = new ObjectInputStream(
          inputStream);
      String result = (String) inputFromServlet.readObject();
      inputFromServlet.close();
      inputStream.close();
      // show result
      resultField.setText(result);
    } catch (Exception ex) {
      ex.printStackTrace();
    }
}
}

Servlet

import java.io.*;

import javax.servlet.ServletException;
import javax.servlet.http.*;

public class AppletToServlet extends HttpServlet {
// Getting a String object from the applet and send it back.
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
try {
response.setContentType("application/x-java-serialized-object");
InputStream inputStream = request.getInputStream();
ObjectInputStream inputFromApplet = new ObjectInputStream(inputStream);
String string = (String) inputFromApplet.readObject();
// getting string value and passing to applet
OutputStream outputStream = response.getOutputStream();
ObjectOutputStream objectOutputStream = new ObjectOutputStream(outputStream);
objectOutputStream.writeObject(string);
objectOutputStream.flush();
objectOutputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}

web.xml

<web-app>
    <display-name>AppletToServlet</display-name>
    <description> AppletToServlet</description>
        <servlet>
            <servlet-name>applettoservlet</servlet-name>
            <servlet-class>AppletToServlet</servlet-class>
        </servlet>
        <servlet-mapping>
            <servlet-name>applettoservlet</servlet-name>
            <url-pattern>/applettoservlet</url-pattern>
        </servlet-mapping>
</web-app>

Html Code

<html>
    <head>
        <title>AppletToServletExample</title>
    </head>
    <body>
        <applet code="AppletToServletExample" width="700" height="500"></applet>
    </body>
</html>

Applet To Servlet Communication

Applet

AppletContext

AppletStub

AudioClip