🚀 go-pugleaf

 Ahmad Noori <Ahmad.Y.Noori@SAIC.COM> wrote:


> Hello,
 
> I have a txt file that I want to write to it one line at a time.  I
> sometimes want to write in the middle of the file and sometimes at the
> beginning.  Using write(string, int, int), will replace the whole file,
> readline() reads one line at a time, does anyone knowof a  method that
> could write one line at a time.


Try this - there is no way to avoid writing stuff out and in all the
time - sorry, but that's just a fact of life - but hey, disks are
cheap these days...


Paul...


  public static void insertStringInFile(String inFilename,
                                        int lineno,
                                        String lineToBeInserted)
                                        throws IOException
  {
    // temp file

    File outFile = new File("$$$$$$$$.tmp");

     // input

    File inFile = new File(inFilename);

    FileInputStream fis  = new FileInputStream(inFile);

    BufferedReader in = new BufferedReader (new InputStreamReader(fis));

     // output

    FileOutputStream fos = new FileOutputStream(outFile);

    PrintWriter out = new PrintWriter(fos);

    String thisLine = "";


 //   System.out.println("Putils: Insertion is at line *_" + lineno + "_*");


    for(int i = 1; i < lineno; i++)
    {
      thisLine = in.readLine();
      out.println(thisLine);
    }

    out.println(lineToBeInserted);


    while ((thisLine = in.readLine()) != null)
    {
      out.println(thisLine);
    }

    out.flush();
    out.close();
    in.close();

    inFile.delete();
    outFile.renameTo(inFile);


  }






 
> Thanks a lot
> 
> Ahmad Noori
> SAIC
> 
>