新建 文本文档.txt

一个JAVA记事本代码,要很简单的那种

import java.awt.event.ActionListener; 
import java.util.EventListener; 
import java.awt.event.*; 
import java.awt.*; 
import java.io.*; 
import java.lang.*; 
import java.awt.datatransfer.*; 
import javax.swing.*; 


public class MiniEdit extends JFrame implements ActionListener { 

/** 
* Method main 
* 
* 
* @param args 
* 
*/ 
MenuBar menuBar = new MenuBar(); 
Menu file = new Menu("File"), 
edit = new Menu("Edit"), 
help = new Menu("Help"); 

MenuItem[] menuItem ={ 
new MenuItem("New"), 
new MenuItem("Open"), 
new MenuItem("Save"), 
new MenuItem("Exit"), 
new MenuItem("Select All"), 
new MenuItem("Copy"), 
new MenuItem("Cut"), 
new MenuItem("Paste"), 
new MenuItem("Help") 
}; 

TextArea textArea = new TextArea(); 
String fileName = "NoName"; 
Toolkit toolKit = Toolkit.getDefaultToolkit(); 
Clipboard clipboard = toolKit.getSystemClipboard(); 

//opne and close message dialogs 
private FileDialog openFileDialog = 
new FileDialog(this,"Open File",FileDialog.LOAD); 
private FileDialog saveFileDialog = 
new FileDialog(this,"Save File",FileDialog.SAVE); 

public static void main(String[] args) { 
// TODO: Add your code here 
MiniEdit MyEdit = new MiniEdit(); 
MyEdit.show(); 
} 

/** 
* Method MiniEdit 
* 
* 
*/ 
public MiniEdit() { 
// TODO: Add your code here 
setTitle("MiniEdit"); 
setFont(new Font("Times New Roman",Font.PLAIN,15)); 
setBackground(Color.white); 
setSize(500,500); 

setMenuBar(menuBar); 
menuBar.add(file); 
menuBar.add(edit); 
menuBar.add(help); 
for(int i=0;i<4;i++) 
{ 
file.add(menuItem[i]); 
edit.add(menuItem[i+4]); 
} 
help.add(menuItem[8]); 
add(textArea); 

addWindowListener(new WindowAdapter(){ 
public void windowClosing(WindowEvent e){ 
e.getWindow().dispose(); 
System.exit(0); 
} 
}); 

//add actionListener 
for(int i=0;i<menuItem.length;i++) 
{ 
menuItem[i].addActionListener(this); 
} 

} 


/** 
* Method actionPerformed 
* 
* 
* @param e 
* 
*/ 
public void actionPerformed(ActionEvent e) { 
// TODO: Add your code here 
Object eventSource = e.getSource(); 

if(eventSource == menuItem[0])//newItem 
{ 
textArea.setText(""); 
} 

else if(eventSource == menuItem[1])//OpenItem 
{ 
openFileDialog.show(); 
fileName = openFileDialog.getDirectory()+openFileDialog.getFile(); 
if(fileName != null) 
{ 
openFile(fileName); 
} 
} 

else if(eventSource ==menuItem[2])//SaveItem 
{ 
saveFileDialog.show(); 
fileName = saveFileDialog.getDirectory()+saveFileDialog.getFile(); 
if(fileName !=null) 
{ 
writeFile(fileName); 
} 
} 

else if(eventSource==menuItem[3])//exitItem 
{ 
System.exit(0); 
} 

else if(eventSource == menuItem[4])//Select All 
{ 
textArea.selectAll(); 
} 
else if(eventSource == menuItem[5])//copy 
{ 
String text = textArea.getSelectedText(); 
StringSelection selection= new StringSelection(text); 

clipboard.setContents(selection,null); 

} 

else if(eventSource == menuItem[6])//cut 
{ 
String text = textArea.getSelectedText(); 
StringSelection selection = new StringSelection(text); 

clipboard.setContents(selection,null); 
textArea.replaceText("",textArea.getSelectionStart(), 
textArea.getSelectionEnd()); 
} 


else if(eventSource == menuItem[7])//Paste 
{ 
Transferable contents = clipboard.getContents(this); 
if(contents==null) 
return; 
String text; 
text=""; 
try{ 
text = (String)contents.getTransferData(DataFlavor.stringFlavor); 

}catch(Exception ex){} 
textArea.replaceText(text, 
textArea.getSelectionStart(),textArea.getSelectionEnd()); 
} 
else if(eventSource == menuItem[8]) 
{ 
// JOptionPane.showMessageDialog(null,"This is a MiniEdit."); 
} 

} 


//Read file 
public void openFile(String fileName){ 
try{ 
File file = new File(fileName); 
FileReader readIn = new FileReader(file); 
int size = (int)file.length(); 
int charsRead = 0; 
char[] content = new char[size]; 
while(readIn.ready()) 
charsRead += readIn.read(content,charsRead,size-charsRead); 
readIn.close(); 
textArea.setText(new String(content,0,charsRead)); 
}catch(Exception e) 
{ 
System.out.println("Error opening file!"); 
} 
} 

//write file 
public void writeFile(String fileName){ 
try{ 
File file = new File(fileName); 
FileWriter write = new FileWriter(file); 
write.write(textArea.getText()); 
write.close(); 
}catch(Exception e){ 
System.out.println("Error closing file!"); 
} 
} 

}
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