aspose file tools*
The moose likes Applets and the fly likes Applet not working Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login
JavaRanch » Java Forums » Java » Applets
Bookmark "Applet not working" Watch "Applet not working" New topic
Author

Applet not working

ch praveen
Ranch Hand

Joined: Mar 08, 2004
Posts: 67
H Friends,
When I executed a program which captures voice and plays at console, it's working fine. Iam using jdk 1.3. when it comes to browser (IE 5.0, the same program which is now implemented as an applet , is not working. When errors are logged in a file, [IE security options are changed to enable file i/o] it's throwing ClassNotFoundException. When a Html Converter is used so as to enable the browser to use jdk 1.3 and that HTML file is opened, it's not even performming logging now and Iam unable to know whether this approach is making browser to use jdk1.3 and not able to understand why logging (recording errors into file) is not performed . [ As log file is not created ].

Iam listing out programs that are pertaining to the above problem.

------------------------------------------------------------------ [ Listing 1 ]

// A java Program which can be run at console to capture a voice and to play it. [ obtained from www.developer.com ]

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import javax.sound.sampled.*;

public class AudioCapture01 extends JFrame {

boolean stopCapture = false;
ByteArrayOutputStream
byteArrayOutputStream;
AudioFormat audioFormat;
TargetDataLine targetDataLine;
AudioInputStream audioInputStream;
SourceDataLine sourceDataLine;
static FileOutputStream fout=null;

public static void main(String args[]) {
try {
fout = new FileOutputStream("d:\\audiocapture01.wav");
}catch(Exception ig) { }
new AudioCapture01();
}//end main

public AudioCapture01(){//constructor
final JButton captureBtn =
new JButton("Capture");
final JButton stopBtn =
new JButton("Stop");
final JButton playBtn =
new JButton("Playback");

captureBtn.setEnabled(true);
stopBtn.setEnabled(false);
playBtn.setEnabled(false);

//Register anonymous listeners
captureBtn.addActionListener(
new ActionListener(){
public void actionPerformed(
ActionEvent e){
captureBtn.setEnabled(false);
stopBtn.setEnabled(true);
playBtn.setEnabled(false);
//Capture input data from the
// microphone until the Stop
// button is clicked.
captureAudio();
}//end actionPerformed
}//end ActionListener
);//end addActionListener()
getContentPane().add(captureBtn);

stopBtn.addActionListener(
new ActionListener(){
public void actionPerformed(
ActionEvent e){
captureBtn.setEnabled(true);
stopBtn.setEnabled(false);
playBtn.setEnabled(true);
//Terminate the capturing of
// input data from the
// microphone.
stopCapture = true;
}//end actionPerformed
}//end ActionListener
);//end addActionListener()
getContentPane().add(stopBtn);

playBtn.addActionListener(
new ActionListener(){
public void actionPerformed(
ActionEvent e){
//Play back all of the data
// that was saved during
// capture.
playAudio();
}//end actionPerformed
}//end ActionListener
);//end addActionListener()
getContentPane().add(playBtn);

getContentPane().setLayout(
new FlowLayout());
setTitle("Capture/Playback Demo");
setDefaultCloseOperation(
EXIT_ON_CLOSE);
setSize(250,70);
setVisible(true);
}//end constructor

//This method captures audio input
// from a microphone and saves it in
// a ByteArrayOutputStream object.
private void captureAudio(){
try{
//Get everything set up for
// capture
audioFormat = getAudioFormat();
DataLine.Info dataLineInfo =
new DataLine.Info(
TargetDataLine.class,
audioFormat);
targetDataLine = (TargetDataLine)
AudioSystem.getLine(
dataLineInfo);
targetDataLine.open(audioFormat);
targetDataLine.start();

//Create a thread to capture the
// microphone data and start it
// running. It will run until
// the Stop button is clicked.
Thread captureThread =
new Thread(
new CaptureThread());
captureThread.start();
} catch (Exception e) {
System.out.println(e);
System.exit(0);
}//end catch
}//end captureAudio method

//This method plays back the audio
// data that has been saved in the
// ByteArrayOutputStream
private void playAudio() {
try{
//Get everything set up for
// playback.
//Get the previously-saved data
// into a byte array object.
byte audioData[] =
byteArrayOutputStream.
toByteArray();
//Get an input stream on the
// byte array containing the data
InputStream byteArrayInputStream
= new ByteArrayInputStream(
audioData);
AudioFormat audioFormat =
getAudioFormat();
audioInputStream =
new AudioInputStream(
byteArrayInputStream,
audioFormat,
audioData.length/audioFormat.
getFrameSize());
DataLine.Info dataLineInfo =
new DataLine.Info(
SourceDataLine.class,
audioFormat);
sourceDataLine = (SourceDataLine)
AudioSystem.getLine(
dataLineInfo);
sourceDataLine.open(audioFormat);
sourceDataLine.start();

//Create a thread to play back
// the data and start it
// running. It will run until
// all the data has been played
// back.
Thread playThread =
new Thread(new PlayThread());
playThread.start();
} catch (Exception e) {
System.out.println(e);
System.exit(0);
}//end catch
}//end playAudio

//This method creates and returns an
// AudioFormat object for a given set
// of format parameters. If these
// parameters don't work well for
// you, try some of the other
// allowable parameter values, which
// are shown in comments following
// the declarations.
private AudioFormat getAudioFormat(){
float sampleRate = 8000.0F;
//8000,11025,16000,22050,44100
int sampleSizeInBits = 16;
//8,16
int channels = 2;
//1,2
boolean signed = true;
//true,false
boolean bigEndian = false;
//true,false
return new AudioFormat(
sampleRate,
sampleSizeInBits,
channels,
signed,
bigEndian);
}//end getAudioFormat
//===================================//

//Inner class to capture data from
// microphone
class CaptureThread extends Thread{
//An arbitrary-size temporary holding
// buffer
byte tempBuffer[] = new byte[10000];
public void run(){
byteArrayOutputStream =
new ByteArrayOutputStream();
stopCapture = false;
try{//Loop until stopCapture is set
// by another thread that
// services the Stop button.
while(!stopCapture){
//Read data from the internal
// buffer of the data line.
int cnt = targetDataLine.read(
tempBuffer,
0,
tempBuffer.length);
if(cnt > 0){
//Save data in output stream
// object.
byteArrayOutputStream.write(
tempBuffer, 0, cnt);
fout.write(tempBuffer, 0, cnt);
fout.flush();
}//end if
}//end while
byteArrayOutputStream.close();
}catch (Exception e) {
System.out.println(e);
System.exit(0);
}//end catch
}//end run
}//end inner class CaptureThread
//===================================//
//Inner class to play back the data
// that was saved.
class PlayThread extends Thread{
byte tempBuffer[] = new byte[10000];

public void run(){
try{
int cnt;
//Keep looping until the input
// read method returns -1 for
// empty stream.
while((cnt = audioInputStream.
read(tempBuffer, 0,
tempBuffer.length)) != -1){
if(cnt > 0){
//Write data to the internal
// buffer of the data line
// where it will be delivered
// to the speaker.
sourceDataLine.write(
tempBuffer, 0, cnt);
}//end if
}//end while
//Block and wait for internal
// buffer of the data line to
// empty.
sourceDataLine.drain();
sourceDataLine.close();
}catch (Exception e) {
System.out.println(e);
System.exit(0);
}//end catch
}//end run
}//end inner class PlayThread
//===================================//

}//end outer class AudioCapture01.java

------------------------------------------------------------------ [ Listing 2 ]
// The above progam is implemented as an applet.
/*
<applet code = "AudioCaptureApplet" height=200 width=400>
</applet>
*/
import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import javax.sound.sampled.*;

public class AudioCaptureApplet extends Applet {

boolean stopCapture = false;
ByteArrayOutputStream byteArrayOutputStream;
AudioFormat audioFormat;
TargetDataLine targetDataLine;
AudioInputStream audioInputStream;
SourceDataLine sourceDataLine;
FileOutputStream fout = null;
FileOutputStream flog = null;

public void init() {
try
{
fout = new FileOutputStream("d:\\audiocaptureapplet.au");
flog = new FileOutputStream("d:\\audiocaptureapplet.log");
}
catch ( Exception ig)
{
}

buildLayout();
}

private void buildLayout(){
final Button captureBtn = new Button("Capture");
final Button stopBtn = new Button("Stop");
final Button playBtn = new Button("Playback");

captureBtn.setEnabled(true);
stopBtn.setEnabled(false);
playBtn.setEnabled(false);

//Register anonymous listeners
captureBtn.addActionListener(
new ActionListener(){
public void actionPerformed(
ActionEvent e){
captureBtn.setEnabled(false);
stopBtn.setEnabled(true);
playBtn.setEnabled(false);
//Capture input data from the
// microphone until the Stop
// button is clicked.
try {
flog.write("\n\nTrying to capture data".getBytes());
flog.flush();
}catch(Exception ig) { }
captureAudio();
}//end actionPerformed
}//end ActionListener
);//end addActionListener()
add(captureBtn);

stopBtn.addActionListener(
new ActionListener(){
public void actionPerformed(
ActionEvent e){
captureBtn.setEnabled(true);
stopBtn.setEnabled(false);
playBtn.setEnabled(true);
//Terminate the capturing of
// input data from the
// microphone.
try {
flog.write("\n\nTrying to stop capture by setting stopCapture = true".getBytes());
flog.flush();
}catch(Exception ig) { }
stopCapture = true;
}//end actionPerformed
}//end ActionListener
);//end addActionListener()
add(stopBtn);

playBtn.addActionListener(
new ActionListener(){
public void actionPerformed(
ActionEvent e){
//Play back all of the data
// that was saved during
// capture.
try {
flog.write("\n\nTrying to play captured data".getBytes());
flog.flush();
}catch(Exception ig) { }
playAudio();
}//end actionPerformed
}//end ActionListener
);//end addActionListener()
add(playBtn);

setLayout(new FlowLayout());
}

//This method captures audio input
// from a microphone and saves it in
// a ByteArrayOutputStream object.
private void captureAudio(){
try{
//Get everything set up for
// capture
audioFormat = getAudioFormat();
DataLine.Info dataLineInfo =
new DataLine.Info(
TargetDataLine.class,
audioFormat);
targetDataLine = (TargetDataLine)
AudioSystem.getLine(
dataLineInfo);
targetDataLine.open(audioFormat);
targetDataLine.start();

//Create a thread to capture the
// microphone data and start it
// running. It will run until
// the Stop button is clicked.
Thread captureThread =
new Thread(
new CaptureThread());
captureThread.start();
} catch (Exception e) {
System.err.println(e);
try {
flog.write( ("\n\nError during capturing audio, " + e).getBytes() );
flog.flush();
}catch(Exception ig) { }
}//end catch
}//end captureAudio method

//This method plays back the audio
// data that has been saved in the
// ByteArrayOutputStream
private void playAudio() {
try{
//Get everything set up for
// playback.
//Get the previously-saved data
// into a byte array object.
byte audioData[] =
byteArrayOutputStream.
toByteArray();
//Get an input stream on the
// byte array containing the data
InputStream byteArrayInputStream
= new ByteArrayInputStream(
audioData);
AudioFormat audioFormat =
getAudioFormat();
audioInputStream =
new AudioInputStream(
byteArrayInputStream,
audioFormat,
audioData.length/audioFormat.
getFrameSize());
DataLine.Info dataLineInfo =
new DataLine.Info(
SourceDataLine.class,
audioFormat);
sourceDataLine = (SourceDataLine)
AudioSystem.getLine(
dataLineInfo);
sourceDataLine.open(audioFormat);
sourceDataLine.start();

//Create a thread to play back
// the data and start it
// running. It will run until
// all the data has been played
// back.
Thread playThread =
new Thread(new PlayThread());
playThread.start();
} catch (Exception e) {
System.err.println(e);
try {
flog.write( ("\n\nError during playing audio, " + e).getBytes() );
flog.flush();
}catch(Exception ig) { }
}//end catch
}//end playAudio

//This method creates and returns an
// AudioFormat object for a given set
// of format parameters. If these
// parameters don't work well for
// you, try some of the other
// allowable parameter values, which
// are shown in comments following
// the declarations.
private AudioFormat getAudioFormat(){
float sampleRate = 8000.0F;
//8000,11025,16000,22050,44100
int sampleSizeInBits = 16;
//8,16
int channels = 2;
//1,2
boolean signed = true;
//true,false
boolean bigEndian = false;
//true,false
return new AudioFormat(
sampleRate,
sampleSizeInBits,
channels,
signed,
bigEndian);
}//end getAudioFormat
//===================================//

//Inner class to capture data from
// microphone
class CaptureThread extends Thread{
//An arbitrary-size temporary holding
// buffer
byte tempBuffer[] = new byte[10000];
public void run(){
byteArrayOutputStream =
new ByteArrayOutputStream();
stopCapture = false;
try{//Loop until stopCapture is set
// by another thread that
// services the Stop button.
while(!stopCapture){
//Read data from the internal
// buffer of the data line.
int cnt = targetDataLine.read(
tempBuffer,
0,
tempBuffer.length);
if(cnt > 0){
//Save data in output stream
// object.
byteArrayOutputStream.write(
tempBuffer, 0, cnt);
}//end if
}//end while
byteArrayOutputStream.close();
}catch (Exception e) {
System.err.println(e);
try {
flog.write( ("\n\nError in capture thread, " + e).getBytes() );
flog.flush();
}catch(Exception ig) { }
}//end catch
}//end run
}//end inner class CaptureThread
//===================================//
//Inner class to play back the data
// that was saved.
class PlayThread extends Thread{
byte tempBuffer[] = new byte[10000];

public void run(){
try{
int cnt;
//Keep looping until the input
// read method returns -1 for
// empty stream.
while((cnt = audioInputStream.
read(tempBuffer, 0,
tempBuffer.length)) != -1){
if(cnt > 0){
//Write data to the internal
// buffer of the data line
// where it will be delivered
// to the speaker.
sourceDataLine.write(
tempBuffer, 0, cnt);
fout.write(tempBuffer, 0, cnt);
fout.flush();
}//end if
}//end while
//Block and wait for internal
// buffer of the data line to
// empty.
sourceDataLine.drain();
sourceDataLine.close();
}catch (Exception e) {
System.err.println(e);
try {
flog.write( ("\n\nError in play thread, " + e).getBytes() );
flog.flush();
}catch(Exception ig) { }
}//end catch
}//end run
}//end inner class PlayThread
//===================================//

}//end outer class AudioCaptureApplet.java

------------------------------------------------------------------ [ Listing 3 ]
<!-- Html file which loads this applet by using browsers default JRE -->
<!-- INCLUSION OF APPLET BY THIS HTML FILE IS REPORTING, ClassNotFoundException. -->

<APPLET CODE = "AudioCaptureApplet.class" WIDTH = "600" HEIGHT = "250">
</APPLET>

------------------------------------------------------------------ [ Listing 4 ]
<!-- Html file, changed by means of HTML Converter to include JRE 1.3 -->
<!-- INCLUSION OF APPLET BY THIS HTML FILE IS NOT EVEN PERFORMING LOGGING. -->

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Audio Capture Applet</title>
</head>

<body>

<!--"CONVERTED_APPLET"-->
<!-- CONVERTER VERSION 1.3 -->
<OBJECT classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93"
WIDTH = "600"
HEIGHT = "250"
ALT = "Your browser is not configured to view the applet. Please install JRE 1.3"
codebase="http://java.sun.com/products/plugin/1.3/jinstall-13-win32.cab#Version=1,3,0,0">

<PARAM NAME = CODE VALUE = "AudioCaptureApplet.class" >

<PARAM NAME="type" VALUE="application/x-java-applet;version=1.3">
<PARAM NAME="scriptable" VALUE="false">
<PARAM NAME = "title" VALUE ="Audio Capture Applet">
<COMMENT>
<EMBED
type="application/x-java-applet;version=1.3"
CODE = "AudioCaptureApplet.class"
ALT = "Your browser is not configured to view the applet. Please install JRE 1.3"
WIDTH = "600"
HEIGHT = "250"
title = "Audio Capture Applet"
scriptable=false
pluginspage="http://java.sun.com/products/plugin/1.3/plugin-install.html">
<NOEMBED>
</COMMENT>
</NOEMBED>
</EMBED>
</OBJECT>

<!--
<APPLET CODE = "AudioCaptureApplet.class" WIDTH = "600" HEIGHT = "250" ALT = "Your browser is not configured to view the applet. Please install JRE 1.3">
</APPLET>
-->
<!--"END_CONVERTED_APPLET"-->

</body>
</html>
--------------------------------------------------------------------
Deployment::
Include the applet and html files in
the roor dir. of Tomcat, and switch to those html
files after starting tomcat
eg:: http://localhost:8080/audiocapture_n.html
--------------------------------------------------------------------

Kindly, post ur comments asap. Very urgent .....

Regards,
Ch.Praveen Kumar.
 
 
subject: Applet not working