Question

I have a method that get text from a JTextArea, create a file and write text on it as code below:

public void createTxt() {

    TxtFilter txt = new TxtFilter();

    JFileChooser fSave = new JFileChooser();

    fSave.setFileFilter(txt);
    int result = fSave.showSaveDialog(this);
    if(result == JFileChooser.APPROVE_OPTION) {
        File sFile = fSave.getSelectedFile();
        FileFilter selectedFilter = fSave.getFileFilter();

        String file_name = sFile.getName();
        String file_path = sFile.getParent();

        try{
            if(!sFile.exists()) {
                sFile.createNewFile();
                BufferedWriter out = new BufferedWriter(new FileWriter(sFile));
                out.write(jTextArea1.getText());
                out.close();
                JOptionPane.showMessageDialog(null, "Warning file • " + file_name + " • created succesfully in \n" + file_path);    
            } else {
                String message = "File • " + file_name + " • already exist in \n" + file_path + ":\n" + "Do you want to overwrite?";
                String title = "Warning";
                int reply = JOptionPane.showConfirmDialog(null, message, title, JOptionPane.YES_NO_OPTION);
                if(reply == JOptionPane.YES_OPTION){
                    sFile.delete();
                    sFile.createNewFile();
                    BufferedWriter out = new BufferedWriter(new FileWriter(sFile));
                    out.write(jTextArea1.getText());
                    out.close();
                    JOptionPane.showMessageDialog(null, "File • " + file_name + " • overwritten succesfully in \n" + file_path);

                }
            }
        }
       catch(IOException e) {
           System.out.println("Error");
       }
    }
}

and a txt file filter

public class TxtFilter extends FileFilter{
    @Override
    public boolean accept(File f){
        return f.getName().toLowerCase().endsWith(".txt")||f.isDirectory();
    }
    @Override
    public String getDescription(){
        return "Text files (*.txt)";
    }
}

The file filter for txt works fine but what I want is to add “.txt” extension when I type file name.

How to I have to modify my code?

Answer 1

UPDATE

You pointed me out that the check for existing files doesn’t work. I’m sorry, I didn’t think of it when I suggested you to replace the BufferedWriter line.
Now, replace this:

File sFile = fSave.getSelectedFile();

with:

File sFile = new File(fSave.getSelectedFile()+".txt");

With this replacement, it isn’t now needed to replace the line of BufferedWriter, adding .txt for the extension. Then, replace that line with the line in the code you posted (with BufferedWriter out = new BufferedWriter(new FileWriter(sFile)); instead of BufferedWriter out = new BufferedWriter(new FileWriter(sFile+".txt"));).

Now the program should work as expected.

I forgot to mention that you have to comment the line:

sFile.createNewFile();

In this way, you’re creating an empty file, with the class File.

Just after this line, there is: BufferedWriter out = new BufferedWriter(new FileWriter(sFile));.
With this line, you are creating again the same file. The writing procedure is happening two times! I think it’s useless to insert two instructions that are doing the same task.

Also, on the BufferedWriter constructor, you can append a string for the file name (it isn’t possible on File constructor), that’s the reason why I added +".txt" (the extension) to sFile.