Share on Google+Share on Google+

Java JMenuItem to perform file operations

Advertisement
In this tutorial, you will learn how to use JMenuItem class to perform file operations.

Java JMenuItem to perform file operations

In this tutorial, you will learn how to use JMenuItem class to perform file operations.

Java Swing introduced the JMenuBar Component. Swing provides support for pull-down and popup menus. A JMenubar can contain several JMenu's. Each of the JMenu's can contain a series of JMenuItem's that you can select. Here is a simple JMenuItem example in java swing through which you can perform open and save operations on File.

Example:

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

public class SwingMenu{
    final JTextArea txtArea=new JTextArea(0,0); 
    JFrame frame = new JFrame();
    String Filename;
    String filename;
  public static void main(String[] args) {
  SwingMenu s = new SwingMenu();
  }
   void ReadFile()
         {
         BufferedReader d;
         StringBuffer sb = new StringBuffer();
         try
             {
             d = new BufferedReader(new FileReader(filename));
             String line;
             while((line=d.readLine())!=null)
             sb.append(line + "\n");
             txtArea.setText(sb.toString());
             d.close();
         }
         catch(FileNotFoundException fe)
             {
             System.out.println("File not Found");
         }
         catch(IOException ioe){}
     }

  public SwingMenu(){


   JScrollPane scroll=new JScrollPane(txtArea);
  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  JMenuBar menubar = new JMenuBar();
  JMenu filemenu = new JMenu("File");
  JMenuItem fileItem1 = new JMenuItem("Open");
  JMenuItem fileItem2 = new JMenuItem("Save");
  filemenu.add(fileItem1);
  filemenu.add(fileItem2);
  menubar.add(filemenu);

      fileItem1.addActionListener(new ActionListener(){
          public void actionPerformed(ActionEvent e)
             {
             FileDialog fd = new FileDialog(frame, "select File",FileDialog.LOAD);
             fd.show();
             if (fd.getFile()!=null)
                 {
                 filename = fd.getDirectory() + fd.getFile();
                 frame.setTitle(filename);
                 ReadFile();
             }
             txtArea.requestFocus();
         }
      });


      fileItem2.addActionListener(new ActionListener(){
           public void actionPerformed(ActionEvent e)
             {
             FileDialog fd = new FileDialog(frame,"Save File",FileDialog.SAVE);
             fd.show();
             if (fd.getFile()!=null)
                 {
                 filename = fd.getDirectory() + fd.getFile();
                 frame.setTitle(filename);
                 try
                     {
                     DataOutputStream d = new DataOutputStream(new FileOutputStream(filename));
                     String line = txtArea.getText();
                     BufferedReader br = new BufferedReader(new StringReader(line));
                     while((line = br.readLine())!=null)
                         {
                         d.writeBytes(line + "\r\n");

                     }
                     d.close();
                 }
                 catch(Exception ex)
                     {
                     System.out.println("File not found");
                 }
                 txtArea.requestFocus();
             }
         }
          });

  frame.setJMenuBar(menubar);
  frame.add(txtArea);
  frame.setSize(400,400);
  frame.setVisible(true);
  }
}

Advertisements

Advertisement

Posted on: December 12, 2012 If you enjoyed this post then why not add us on Google+? Add us to your Circles

Share this Tutorial Follow us on Twitter, or add us on Facebook or Google Plus to keep you updated with the recent trends of Java and other open source platforms.