Applet working in Eclipse but not in browser

[leeloo]

Hello,

2 things first: 1. sorry for the english mistakes
2. i'm new to java

Ok, so i have to create an interface between a microcontroller connected to the computer via a serial cable ( RS 232 ) and the end user. I did this with an applet that i wanted to implement in a simpe web page an publish it on the big world wide web.

I created 2 classes: SimpleRead and Applet

SimpleRead takes care of the serial comunication and determines a variable called "temp" ( it is a temperature and it is a string ). At first i wrote this variable to the consol and everything was perfect.

Then i created the applet class with an textField for the temperature. This calls the method SimpleRead. The actual writing of the temperature in the textField happens in the class SimpleRead.

When i run the project in Eclipse it works perfect, meening that every 1-2 seconds the temperature is written in the textFiled again in the applet.

The problem is that in the web page the textField remains empty.....

Anyone any ideas on what should I change? Thanks in advance

I don't know how much it will help if i write the code... but i will do so. So:

SimpleRead.java

import java.io.*;
import java.util.*;
import gnu.io.*;
import java.awt.*;
import java.applet.*;

public class SimpleRead implements Runnable, SerialPortEventListener
{
    public static CommPortIdentifier 	portId;
    public static Enumeration	      	portList;
    public InputStream		      		inputStream;
    public OutputStream           		outputStream;
    public SerialPort		      		serialPort;
    public Thread		      			readThread;
    public Thread 			  			writeThread;
    static String 				emma=new String(" ");
    int 						numBytes;
    InputStreamReader 			in;
    char[] 						con=new char[100];
    String						var;
    char						var2;
    int 						j=0;
   public static String temp,but1,but2,led1,led2; 

    /* Constructor declaration*/
    
   TextField t,b1,b2;
   
    public SimpleRead(TextField textF, TextField text1, TextField text2) 
    {
    	t=textF;
    	b1=text1;
    	b2=text2;
    	
    	try 
    	{
    		serialPort = (SerialPort) portId.open("SimpleReadApp", 20000); 
    	} catch (PortInUseException e) {}

    	try
    	{
    		inputStream = serialPort.getInputStream();
    		outputStream = serialPort.getOutputStream();
    	} catch (IOException e) {}

    	try 	
    	{
    		serialPort.addEventListener(this);
    	} catch (TooManyListenersException e) {}

    	serialPort.notifyOnDataAvailable(true);

    	try 
    	{
    		serialPort.setSerialPortParams(19200, SerialPort.DATABITS_8,SerialPort.STOPBITS_1,SerialPort.PARITY_NONE);
    	} catch (UnsupportedCommOperationException e) {}

    	readThread = new Thread(this); 
    	writeThread =new Thread(this);
	
    	readThread.start();
    	writeThread.start();
    }

  
    
    public void run() 
    {
    	try 
    	{
    		Thread.sleep(20000);
    	} catch (InterruptedException e) {}
    } 
    
    @SuppressWarnings("restriction")
    
	public void serialEvent(SerialPortEvent event) 
    {
    	try{
			String enter = "9\r\n";
	
			System.out.println("Trimis: "+ enter+"\r\n");
			outputStream.write(enter.getBytes());
			emma="0";
			} catch (IOException e) {}	
		
    	switch (event.getEventType()) 
    	{
    		case SerialPortEvent.BI:

    		case SerialPortEvent.OE:

    		case SerialPortEvent.FE:

    		case SerialPortEvent.PE:

    		case SerialPortEvent.CD:

    		case SerialPortEvent.CTS:

    		case SerialPortEvent.DSR:

    		case SerialPortEvent.RI:

    		case SerialPortEvent.OUTPUT_BUFFER_EMPTY:
    			break;

    		case SerialPortEvent.DATA_AVAILABLE:
    				byte[] readBuffer = new byte[300];
    				
    				try 
    				{
    					while (inputStream.available() > 0)
    					{
    						numBytes = inputStream.read(readBuffer); 
    					} 
  
    					for(int i=0; i<numBytes; i++)  
    					{
    						System.out.print((char) (readBuffer[i]));    						
    						var2=(char) readBuffer[i]; // 1 letter at a time
    						con[i]=var2; // building the words one by one
    					}
    					
    					var=new String(con);
    					emma+=var; // putting all the words together
    					
    				} catch (IOException e) {}
	    
    				break;
    	}
    	
  
	       		int index_temp_start=emma.indexOf("temp:")+5;
	       		int index_temp_end=emma.indexOf("\r\npb1:");
	       		
	       		temp=emma.substring(index_temp_start,index_temp_end);
	       		
	       		//System.out.println(" ");
	       		//System.out.print(" !!!!! Temperatura:");
	       		//System.out.print(temp);
	       		//System.out.println(" ");
	       		
	       		t.setText(temp);
	       		
	       		index_temp_start=emma.indexOf("pb1:")+4;
	       		index_temp_end=emma.indexOf("\r\npb2:");
	       		
	       		if(emma.substring(index_temp_start,index_temp_end).indexOf("rel") !=-1)
	       	
	       			but1="Relesed";
	       		else
	       			if(emma.substring(index_temp_start,index_temp_end).indexOf("pre") !=-1)
	       				but1="Pressed";
	       		
	       		b1.setText(but1);
	       		
	       		index_temp_start=emma.indexOf("pb2:")+4;
	       		index_temp_end=emma.indexOf("\r\nled1");
	       		
	       		if(emma.substring(index_temp_start,index_temp_end).indexOf("rel") !=-1)
	    	       	
	       			but2="Relesed";
	       		else
	       			if(emma.substring(index_temp_start,index_temp_end).indexOf("pre") !=-1)
	       				but2="Pressed";
	    
	       		b2.setText(but2);
	 
	}
}

NotHelloAgain.java - the applet class of couse :D

import java.io.*;
import java.util.*;

import gnu.io.*;

import java.awt.*;
import java.applet.*;

	public class NotHelloAgain extends Applet
	{
		static TextField temperatura;
		static TextField buton2;
		static TextField buton1;
		
		public void init()
		{
			boolean		      portFound = false;
	    	String		      defaultPort = "COM8";
			
	    	setLayout(null);
			
			Label label;
		    label = new Label("Temperatura");
		    label.setBounds(20,20,90,15); 
		    add(label);
		    
			 temperatura=new TextField(15); 
			 temperatura.setBounds(120,20,100,20); 
			add(temperatura);
			
			Label label2;
		    label2 = new Label("Buton 1"); 
		    label2.setBounds(20,60,90,15); 
		    add(label2);
		    
			buton1=new TextField(15);
			buton1.setBounds(120,60,100,20);
			add(buton1);
			
			Label label3;
		    label3 = new Label("Buton 2");
		    label3.setBounds(20,100,90,15); 
		    add(label3);
		    
			buton2=new TextField(15);   
			buton2.setBounds(120,100,100,20);
			add(buton2);
			
			
	    	SimpleRead.portList = CommPortIdentifier.getPortIdentifiers();   

	    	while (SimpleRead.portList.hasMoreElements()) 					
	    	{
	    		SimpleRead.portId = (CommPortIdentifier) SimpleRead.portList.nextElement();
	    		if (SimpleRead.portId.getPortType() == CommPortIdentifier.PORT_SERIAL)
	    		{
	    			if (SimpleRead.portId.getName().equals(defaultPort))  
	    			{
	    				System.out.println("Found port: "+defaultPort);  
	    				portFound = true;
	    				SimpleRead reader = new SimpleRead(temperatura,buton1,buton2); 	
	    			} 
	    		} 
	    	}
	    	
	    	if (!portFound)
	    	{
	    		System.out.println("port " + defaultPort + " not found.");
	    	}	 
			
		}
		public void paint(Graphics g)
		{
			  g.drawRect(10,10,240,160);

		}
		}

[Fubarable]

You don't want to ignore exceptions:

catch (IOException e) {}

Otherwise how will you know what's wrong with your program?

[leeloo]

I know you're wright about the exceptions... and that i should tell my programm to do something when it cathes errors.

But the program works, as i wrote in the post :) The temperature is displayed in the TextFiled in the applet. My problem is that it doesn't work in the browser...

I may be wrong of course :), but i don't think that it has anything to do with the exceptions that could appear :)

[Fubarable]

I know you're wright about the exceptions... and that i should tell my programm to do something when it cathes errors.

But the program works, as i wrote in the post :) The temperature is displayed in the TextFiled in the applet. My problem is that it doesn't work in the browser...

I may be wrong of course :), but i don't think that it has anything to do with the exceptions that could appear :)

If it were me, until I know why it's not working, I would avoid making any assumptions. I would make sure to catch all exceptions and then look at the Java Console of my browser to make sure that no exceptions have been caught and sent.

[Norm]

Did you look in the browser's java console?
Many errors will be written there.

[Fubarable]

Did you look in the browser's java console?
Many errors will be written there.

Not if he ignores exceptions. :rolleyes:

[Norm]

I was thinking of the JVM not finding classes that are present in the IDE.

[Fubarable]

True. Good point.