Question

Hi I’m using the below method to write to a file from the Jtextarea and I call this method every 30 second within a Timer but instead to add only new line in file it rewrite the entire lines contained in Jtextarea so then I have duplicate lines. I want to avoid this and update the file just with new lines. Could you help me please.

public void loger() {

    FileWriter writer = null;

    try {
        writer = new FileWriter("MBM_Log_"+date()+".txt" , true);
        textArea.write(writer);

        } catch (IOException exception) {
        System.err.println("log error");
        exception.printStackTrace();

        } finally {
        if (writer != null) {
            try {
                writer.close();
                } catch (IOException exception) {
                System.err.println("Error closing writer");
                exception.printStackTrace();
            }
        }

    }

  }

Answer 1

I changed my code instead to write to the file from the Jtextarea I write the string (LOG) directly to the file. My method loger() become as below :
public void loger (String texLine){

    FileWriter writer = null;

    try {       
        writer = new FileWriter("MBM_Log_"+date()+".txt" , true);
        PrintWriter out = new PrintWriter(writer);
        out.printf("%s"+"%n", texLine);
                    out.close();
        } catch (IOException exception) {
        System.err.println("log error");
        exception.printStackTrace();
        }

    finally {
        if (writer != null) {
            try {
                writer.close();
                } catch (IOException exception) {
                System.err.println("Error closing writer");
                exception.printStackTrace();
            }
        }
    }

    }

And then then I write the log to the Jtextarea to be displayed in GUI and calling the method loger() to write to the file e.g:

textArea.append(dateTime()+ ” : Alarm sound muted by the Operator from the Menu Bar “);

loger(dateTime()+ ” : Alarm sound muted by the Operator from the Menu Bar “);

By this way I have the logs in Jtextarea and in the file. My problem is resolved when I restart the application the file is not erased and the new log is added to the file.
Thanks to all.