[Java] implements the preparation of a simple notepad.

Document directory

• Notepad legend
• Open legend:
• Save as legend

Notebook function Introduction 1. New: Clear notepad. 2. Open: any text file in the notebook can be opened. 3. Save: Save the file to the current folder. 4. Save as: Save the file to any location. 5. Exit: confirm whether to save the content before exiting. [NOTE: When "save" and "Save as", you should specify the file suffix, for example, xxx.txt.] to open any text file in the notebook, you need to use filedialog in the filedialog class. load );

FileDialog fd = new FileDialog (this, "Open", FileDialog.LOAD);
fd.setVisible (true);
It is worth noting that when obtaining the file path, the relevant operations are:
String strFile = fd.getDirectory () + fd.getFile ();
Without fd.getDirectory (), only the current folder can be opened. fd.getDirectory () is equivalent to obtaining the absolute path prefix of the file.

After getting the path, you can open and write the file to the text box. See the blog for specific operations: http://blog.csdn.net/oyuntaolianwu/article/details/9429953 Code examples
private void jMenuItem2ActionPerformed (java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
FileDialog fd = new FileDialog (this, "Open", FileDialog.LOAD);
fd.setVisible (true);
String strFile = fd.getDirectory () + fd.getFile ();
if (strFile! = null) {
try {
FileInputStream fis = new FileInputStream (strFile);
byte [] buf = new byte [10 * 1024];
int len = fis.read (buf);
jTextArea1.append (new String (buf, 0, len));
fis.close ();
} catch (Exception e) {
System.out.println ("Failed to open");
}
}
}
Open the legend: Save the file to any location In fact, it is similar to the above operation. It's just that one reads one writes. After obtaining the file path and content, related operations are much easier. Code example:
private void jMenuItem4ActionPerformed (java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
FileDialog fd = new FileDialog (this, "Save As", FileDialog.SAVE);
fd.setVisible (true);
String string1 = jTextArea1.getText ();
String stringfile = fd.getDirectory () + fd.getFile ();
BufferedWriter bWriter = null;
try {
bWriter = new BufferedWriter (new FileWriter (stringfile));
bWriter.write (string1);
bWriter.close ();
} catch (Exception e) {
// TODO Auto-generated catch block
System.out.println ("Save failed");
}
}
Save as legend Notepad code for Notepad
/ *
 * Test_Notepad.java
 *
 * Created on __DATE__, __TIME__
 * /

// package com.test;

import java.awt. *;
import java.io. *;

import javax.swing.JOptionPane;

/ **
 *
 * @author __USER__
 * /
public class Test_Notepad extends javax.swing.JFrame {

/ ** Creates new form Test_Notepad * /
public Test_Notepad (String name) {
super (name);
initComponents ();
setLocation (450, 200);
}

/ ** This method is called from within the constructor to
* initialize the form.
* WARNING: Do NOT modify this code. The content of this method is
* always regenerated by the Form Editor.
* /
// GEN-BEGIN: initComponents
// <editor-fold defaultstate = "collapsed" desc = "Generated Code">
private void initComponents () {

jScrollPane1 = new javax.swing.JScrollPane ();
jTextArea1 = new javax.swing.JTextArea ();
jMenuBar1 = new javax.swing.JMenuBar ();
jMenu1 = new javax.swing.JMenu ();
jMenuItem1 = new javax.swing.JMenuItem ();
jMenuItem2 = new javax.swing.JMenuItem ();
jMenuItem3 = new javax.swing.JMenuItem ();
jMenuItem4 = new javax.swing.JMenuItem ();
jSeparator1 = new javax.swing.JSeparator ();
jSeparator2 = new javax.swing.JSeparator ();
jMenuItem6 = new javax.swing.JMenuItem ();
jMenu2 = new javax.swing.JMenu ();
jMenuItem7 = new javax.swing.JMenuItem ();
jMenuItem8 = new javax.swing.JMenuItem ();
jMenuItem9 = new javax.swing.JMenuItem ();
jMenuItem10 = new javax.swing.JMenuItem ();
jMenuItem11 = new javax.swing.JMenuItem ();

setDefaultCloseOperation (javax.swing.WindowConstants.EXIT_ON_CLOSE);

jTextArea1.setColumns (20);
jTextArea1.setRows (5);
jScrollPane1.setViewportView (jTextArea1);

jMenu1.setText ("\ u6587 \ u4ef6");
jMenu1.setMinimumSize (new java.awt.Dimension (35, 19));

jMenuItem1.setText ("\ u65b0 \ u5efa");
jMenuItem1.addActionListener (new java.awt.event.ActionListener () {
public void actionPerformed (java.awt.event.ActionEvent evt) {
jMenuItem1ActionPerformed (evt);
}
});
jMenu1.add (jMenuItem1);

jMenuItem2.setText ("\ u6253 \ u5f00");
jMenuItem2.addActionListener (new java.awt.event.ActionListener () {
public void actionPerformed (java.awt.event.ActionEvent evt) {
jMenuItem2ActionPerformed (evt);
}
});
jMenu1.add (jMenuItem2);

jMenuItem3.setText ("\ u4fdd \ u5b58");
jMenuItem3.addActionListener (new java.awt.event.ActionListener () {
public void actionPerformed (java.awt.event.ActionEvent evt) {
jMenuItem3ActionPerformed (evt);
}
});
jMenu1.add (jMenuItem3);

jMenuItem4.setText ("\ u53e6 \ u5b58 \ u4e3a");
jMenuItem4.addActionListener (new java.awt.event.ActionListener () {
public void actionPerformed (java.awt.event.ActionEvent evt) {
jMenuItem4ActionPerformed (evt);
}
});
jMenu1.add (jMenuItem4);
jMenu1.add (jSeparator1);
jMenu1.add (jSeparator2);

jMenuItem6.setText ("\ u9000 \ u51fa");
jMenuItem6.addActionListener (new java.awt.event.ActionListener () {
public void actionPerformed (java.awt.event.ActionEvent evt) {
jMenuItem6ActionPerformed (evt);
}
});
jMenu1.add (jMenuItem6);

jMenuBar1.add (jMenu1);

jMenu2.setText ("\ u7f16 \ u8f91");

jMenuItem7.setText ("\ u64a4 \ u9500");
jMenu2.add (jMenuItem7);

jMenuItem8.setText ("\ u526a \ u5207");
jMenu2.add (jMenuItem8);

jMenuItem9.setText ("\ u590d \ u5236");
jMenu2.add (jMenuItem9);

jMenuItem10.setText ("\ u7c98 \ u8d34");
jMenu2.add (jMenuItem10);

jMenuItem11.setText ("\ u5220 \ u9664");
jMenu2.add (jMenuItem11);

jMenuBar1.add (jMenu2);

setJMenuBar (jMenuBar1);

javax.swing.GroupLayout layout = new javax.swing.GroupLayout (
getContentPane ());
getContentPane (). setLayout (layout);
layout.setHorizontalGroup (layout.createParallelGroup (
javax.swing.GroupLayout.Alignment.LEADING) .addComponent (
jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 400,
Short.MAX_VALUE));
layout.setVerticalGroup (layout.createParallelGroup (
javax.swing.GroupLayout.Alignment.LEADING) .addComponent (
jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 279,
Short.MAX_VALUE));

pack ();
} // </ editor-fold>
// GEN-END: initComponents

private void jMenuItem1ActionPerformed (java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
jTextArea1.setText (null);
}

private void jMenuItem4ActionPerformed (java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
FileDialog fd = new FileDialog (this, "Save As", FileDialog.SAVE);
fd.setVisible (true);
String string1 = jTextArea1.getText ();
String stringfile = fd.getDirectory () + fd.getFile ();
BufferedWriter bWriter = null;
try {
bWriter = new BufferedWriter (new FileWriter (stringfile));
bWriter.write (string1);
bWriter.close ();
} catch (Exception e) {
// TODO Auto-generated catch block
System.out.println ("Save failed");
}
}

private void jMenuItem3ActionPerformed (java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
String FileName = JOptionPane.showInputDialog ("Please enter the saved file name:");
String string1 = jTextArea1.getText ();
if (FileName! = null) {
BufferedWriter bWriter = null;
try {
bWriter = new BufferedWriter (new FileWriter (new File (FileName)));
bWriter.write (string1);
bWriter.close ();
} catch (Exception e) {
System.out.println ("Save failed");
}
}
}

private void jMenuItem6ActionPerformed (java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
int result = JOptionPane.showConfirmDialog (null, "Save before exiting?");
if (result == JOptionPane.YES_OPTION) {
String FileName = JOptionPane.showInputDialog ("Please enter the saved file name:");
String string1 = jTextArea1.getText ();
if (FileName! = null) {
BufferedWriter bWriter = null;
try {
bWriter = new BufferedWriter (new FileWriter (new File (
FileName)));
bWriter.write (string1);
bWriter.close ();
} catch (Exception e) {
System.out.println ("Save failed");
}
}
System.exit (0);
} else if (result == JOptionPane.NO_OPTION) {
System.exit (0);
}
}

private void jMenuItem2ActionPerformed (java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
FileDialog fd = new FileDialog (this, "Open", FileDialog.LOAD);
fd.setVisible (true);
String strFile = fd.getDirectory () + fd.getFile ();
if (strFile! = null) {
try {
FileInputStream fis = new FileInputStream (strFile);
byte [] buf = new byte [10 * 1024];
int len = fis.read (buf);
jTextArea1.append (new String (buf, 0, len));
fis.close ();
} catch (Exception e) {
System.out.println ("Failed to open");
}
}
}

public void SaveNotepad () {
String FileName = JOptionPane.showInputDialog ("Please enter the saved file name:");
String string1 = jTextArea1.getText ();
if (FileName! = null) {
BufferedWriter bWriter = null;
try {
bWriter = new BufferedWriter (new FileWriter (new File (FileName)));
bWriter.write (string1);
bWriter.close ();
// Thread.sleep (1000);
} catch (Exception e) {
e.printStackTrace ();
}
}
}

/ **
* @param args the command line arguments
* /
public static void main (String args []) {
java.awt.EventQueue.invokeLater (new Runnable () {
public void run () {
Test_Notepad notepad = new Test_Notepad ("Jue's Notepad");
notepad.setVisible (true);
}
});
}

// GEN-BEGIN: variables
// Variables declaration-do not modify
private javax.swing.JMenu jMenu1;
private javax.swing.JMenu jMenu2;
private javax.swing.JMenuBar jMenuBar1;
private javax.swing.JMenuItem jMenuItem1;
private javax.swing.JMenuItem jMenuItem10;
private javax.swing.JMenuItem jMenuItem11;
private javax.swing.JMenuItem jMenuItem2;
private javax.swing.JMenuItem jMenuItem3;
private javax.swing.JMenuItem jMenuItem4;
private javax.swing.JMenuItem jMenuItem6;
private javax.swing.JMenuItem jMenuItem7;
private javax.swing.JMenuItem jMenuItem8;
private javax.swing.JMenuItem jMenuItem9;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JSeparator jSeparator1;
private javax.swing.JSeparator jSeparator2;
private javax.swing.JTextArea jTextArea1;
// End of variables declaration // GEN-END: variables

}