🚀 go-pugleaf

Lori M Olson [TeamB] wrote:

> George wrote:
> 
>> I want to capture the standard output of a console program written in 
>> C in a
>> JTextArea component.  The code I am running is shown below.  The issue I
>> have is:  it takes inordinately long for the the first line of    
>> output to
>> appear; and when it does all of the ouput (about 20 lines) appears 
>> together.
>> This is not the case if I run the program from the DOS prompt.  Any ideas
>> why the behavior is different when the program is run under control of a
>> Java program?
>>
>>      cycleProcess = rt.exec(command, null, currentDir);
>>         InputStreamReader isr = new
>> InputStreamReader(cycleProcess.getInputStream());
>>         batchLogReader = new LineNumberReader(isr);
>>         outputLine = batchLogReader.readLine();
>>         while (outputLine  != null) {
>>           outputLine = batchLogReader.readLine();
>>           messagesTextArea.setText(messagesTextArea.getText() + "\n" +
>> outputLine);
>>           
>> messagesTextArea.paintImmediately(messagesTextArea.getBounds());
>>         }
>>
>>
> 
> Generally streams don't flush to output until their buffers are full. If 
> you want to see intermediate results, you should use flush().
> 

Oops.  That's not an output stream.  Sorry.

You are doing screen update work in your main thread, which is not going 
to work.  You should investigate the usage of SwingUtilities.invokeLater.

http://java.sun.com/docs/books/tutorial/uiswing/misc/threads.html

-- 

Regards,

Lori Olson [TeamB]