how to detect what user my program is in in java

Question

I am working on a word processor and i need to know what user my program is in so that my program can auto detect it on start and save the files in their my Documents. Im using java. and i have no precode for the directory detect. but in case this helps here is my code:

import javax.swing.*;

import java.io.*;
import java.awt.event.*;
import java.util.*;


@SuppressWarnings("serial")
class Word1 extends JFrame implements ActionListener, KeyListener{
    ClassLoader Idr = this.getClass().getClassLoader();
    static JPanel pnl = new JPanel();
    public static JTextField Title = new JTextField("Document",25);
    static JTextArea Body = new JTextArea("Body", 48, 68);
    public static JScrollPane pane = new JScrollPane(Body);
    JTextField textField = new JTextField();
    JButton saveButton = new JButton("Save File");
    JButton editButton = new JButton("Edit File");
    JButton deleteButton = new JButton("Delete");
    public static String Input = "";
    public static String Input2 = "";
    public static String Text = "";
    public static void main(String[] args){
        @SuppressWarnings("unused")
        Word1 gui = new Word1();
    }
    public void ListB(){
        // Directory path here
        String username = JOptionPane.showInputDialog(getContentPane(), "File to Delete", "New ", JOptionPane.PLAIN_MESSAGE);
        String path = "C:\\Users\\"+username+"\\Documents\\";
        File folder = new File(path);
        File[] listOfFiles = folder.listFiles();

        for (int i = 0; i < listOfFiles.length; i++)
        {

            if (listOfFiles[i].isFile())
            {
                String files = listOfFiles[i].getName();
                if (files.endsWith(".txt") || files.endsWith(".TXT")){
                    ArrayList<String> doclist = new ArrayList<String>();
                    doclist.add(files);
                    System.out.print(doclist);
                    String l = doclist.get(i);
                }

            }
        }
    }
    public Word1()
    {
        ListB();
        setTitle("Ledbetter Word");
        setSize(800, 850);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        add(pnl);
        Body.setLineWrap(true);
        Body.setWrapStyleWord(true);
        Body.setEditable(true);
        Title.setEditable(true);
        Title.addKeyListener(keyListen2);
        saveButton.addActionListener(this);
        editButton.addActionListener(len);
        deleteButton.addActionListener(len2);
        pane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
        Body.addKeyListener(keyListen);
        pnl.add(saveButton);
        pnl.add(editButton);
        pnl.add(deleteButton);
        pnl.add(Title);
        pnl.add(pane);
        setVisible(true);
    }
    KeyListener keyListen = new KeyListener() {
        @Override
        public void keyTyped(KeyEvent e) {
            @SuppressWarnings("unused")
            char keyText = e.getKeyChar();
        }

        @Override
        public void keyPressed(KeyEvent e) {

        }//ignore

        @Override
        public void keyReleased(KeyEvent e) {
            Word1.Input = Body.getText();
        }//ignore
    };
    KeyListener keyListen2 = new KeyListener() {
        @Override
        public void keyTyped(KeyEvent e) {
            @SuppressWarnings("unused")
            char keyText = e.getKeyChar();

        }

        @Override
        public void keyPressed(KeyEvent e) {

        }

        @Override
        public void keyReleased(KeyEvent e) {
            Word1.Input2 = Title.getText();
        }
    };
    public void keyTyped(KeyEvent e) {

    }

    public void keyPressed(KeyEvent e) {

    }

    public void keyReleased(KeyEvent e) {

    }
    @Override
    public void actionPerformed(ActionEvent e) {
        if( e.getSource() == saveButton ){

            try {
                BufferedWriter fileOut = new BufferedWriter(new FileWriter("C:\\Users\\David\\Documents\\"+Title.getText()+".txt"));
                fileOut.write(Word1.Input);
                fileOut.close();
                JOptionPane.showMessageDialog(getParent(), "Successfully saved to your documents", "Save", JOptionPane.INFORMATION_MESSAGE);
            } catch (IOException ECX) {
                JOptionPane.showMessageDialog(getParent(), "There was an error saving your file", "Save-Error", JOptionPane.ERROR_MESSAGE);
            }

        }
    }
    ActionListener len = new ActionListener(){
        @SuppressWarnings({ "resource" })
        public void actionPerformed(ActionEvent e){
            if(e.getSource() == editButton);{
                String filename = JOptionPane.showInputDialog(getParent(), "File to Delete", "Deletion", JOptionPane.PLAIN_MESSAGE);
                Word1.Body.setText("");
                try{
                    FileReader file = new FileReader(filename+".txt");
                    BufferedReader reader = new BufferedReader(file);
                    String Text = "";
                    while ((Text = reader.readLine())!= null )
                    {
                        Word1.Body.append(Text+"\n");
                    }
                    Word1.Title.setText(filename);
                } catch (IOException e2) {
                    JOptionPane.showMessageDialog(getParent(), "Open File Error\nFile may not exist", "Error!", JOptionPane.ERROR_MESSAGE);
                }
            }

        }
    };

    ActionListener len2 = new ActionListener() {
        @Override
        public void actionPerformed(ActionEvent e) {
            if(e.getSource() == deleteButton);{
                String n = JOptionPane.showInputDialog(getParent(), "File to Delete", "Deletion", JOptionPane.PLAIN_MESSAGE);
                Delete(new File(n+".txt"));
            }
        }
    };
    public void Delete(File Files){
        Files.delete();

    }
}

Answer 1

Assuming you are targeting windows (My Documents hint) you can try this.

String myDocumentsPath = System.getProperty("user.home") + "/Documents";