import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.io.*;

public class OpenMenu extends JFrame implements ActionListener{
JMenuBar mb;
JMenu file;
JMenuItem open;
JTextArea ta;
OpenMenu(){
open=new JMenuItem("Open File");
open.addActionListener(this);

file=new JMenu("File");
file.add(open);

mb=new JMenuBar();
mb.setBounds(0,0,800,20);
mb.add(file);
    
ta=new JTextArea(800,800);
ta.setBounds(0,20,800,800);
    
add(mb);
add(ta);

}
public void actionPerformed(ActionEvent e) {
if(e.getSource()==open){
openFile();
}
}

void openFile(){
JFileChooser fc=new JFileChooser();
int i=fc.showOpenDialog(this);

if(i==JFileChooser.APPROVE_OPTION){
File f=fc.getSelectedFile();
String filepath=f.getPath();

displayContent(filepath);

}

}

void displayContent(String fpath){
try{
BufferedReader br=new BufferedReader(new FileReader(fpath));
String s1="",s2="";

while((s1=br.readLine())!=null){
s2+=s1+"\n";
}
ta.setText(s2);
br.close();
}catch (Exception e) {e.printStackTrace();}
}

public static void main(String[] args) {
OpenMenu om=new OpenMenu();
om.setSize(800,800);
om.setLayout(null);
om.setVisible(true);
om.setDefaultCloseOperation(EXIT_ON_CLOSE);
}
}