We closed this forum 18 June 2010. It has served us well since 2005 as the ALPHA forum did before it from 2002 to 2005. New discussions are ongoing at the new URL http://forum.processing.org. You'll need to sign up and get a new user account. We're sorry about that inconvenience, but we think it's better in the long run. The content on this forum will remain online.
Index › Programming Questions & Help › Other Libraries › Creating, Writing, and Appending Files
‹ Previous Topic | Next Topic ›
Page Index Toggle Pages: 1
Creating, Writing, and Appending Files (Read 1721 times)
aenigma
Creating, Writing, and Appending Files
Jan 7th, 2010, 12:03pm  
I am using Processing to visualize data being received from an Arduino board over a standard serial port connection.  I have no problem getting the data to display in a Processing applet (using Interfascia) or sending serial commands back to the Arduino. What I would like to do is save this data to a file on the PC.  I have actually been able to do that, however I couldn't figure out how to open an existing file to append to it so I ended up making one file for each string of characters.  I can write whatever I want to one file while I have it open, but if I were to re-start the program or close the file, I wasn't able to append to it.  What would actually be perfect is something like the Xlsreader if it could write since my data is best saved as a spreadsheet. Any suggestions for updating or appending to an existing file?  The program would need to check if it exists - if not then create the file and write the data; if so then append it with new data.

Thanks!
Back to top
 
 
PhiLho 
Re: Creating, Writing, and Appending Files
Reply #1 - Jan 7th, 2010, 12:50pm  
Code:
    String[] strings = { "One", "Two", "Three" };
    String fileName = "D:/temp/P5_O.txt";
    PrintWriter pw = null;
    try
    { 
	pw = new PrintWriter(new FileWriter(m_fileName, true));
	for (int i = 0; i < strings.length; i++) 
	{
	  pw.println(strings[i]);
	}
    } 
    catch (IOException e) 
    { 
	e.printStackTrace(); // Dump and primitive exception handling...
    }
    finally
    {
	if (pw != null)
	{
	  pw.close();
	}
    }

Warning: error checking is quite minimal in this code! To be improved...
Back to top
« Last Edit: Jan 21st, 2010, 9:35am by PhiLho  »  
WWW  
Cedric
Re: Creating, Writing, and Appending Files
Reply #2 - Jan 7th, 2010, 12:55pm  
i guess thats the same question, PhiLho already answered there : http://processing.org/discourse/yabb2/?num=1251025598
Back to top
 
... twitter.com/CedricKiefer
WWW CedricKiefer 9570393 CedricKiefer  
PhiLho 
Re: Creating, Writing, and Appending Files
Reply #3 - Jan 7th, 2010, 10:01pm  
Ah, for once I don't point out to a previous thread!  Tongue
I wrote in that thread that there are several ways to do that, I shown here another one (closer of the way Processing writes lines in files).
Back to top
 
WWW  
Page Index Toggle Pages: 1
‹ Previous Topic | Next Topic ›