Java simply implements copy, paste and cut function code sharing

Without further ado, let’s go straight to the code. Friends, please read the comments carefully.

Copy the code code as follows:
/*Simple copy, cut and paste function operations:
Copy test: Enter text, select text, click Copy, then place the cursor on the TextArea on the right, click Paste. Cut test: Enter text, select text, then place the cursor on the TextArea on the right, click Cut.
*/
import javax.swing.*;
import java.awt.*;
import java.awt.datatransfer.*;
import java.awt.event.*;
public class Demo implements ActionListener
{
private JFrame jf;
private JPanel p1, p2, p3; //top, middle and bottom
private JLabel title;
private JTextArea edit,showMsg;
private JButton copy,paste,cut;
Clipboard clipboard;//Get the system clipboard.

publicDemo()
{
this.init();
}
//interface initialization
public void init()
{
jf = new JFrame("Copy and Paste");
p1 = new JPanel(); //Storage title
p2 = new JPanel();//Storage JTextArea showMsg
p3 = new JPanel(); //Storage button
title = new JLabel("Copy, Paste and Cut Demo");
edit = new JTextArea("Please enter content",15,25);
edit.setLineWrap(true);
showMsg = new JTextArea(15,25);
showMsg.setLineWrap(true);
showMsg.setEnabled(false);
copy = new JButton("Copy");
paste = new JButton("Paste");
cut = new JButton("cut");
clipboard = jf.getToolkit().getSystemClipboard();

p1.setLayout(new FlowLayout());
p1.setSize(599,30);
p1.add(title);

p2.setLayout(new FlowLayout());
p2.setBackground(Color.gray);
p2.add(edit);
p2.add(showMsg);

p3.setLayout(new FlowLayout());
p3.add(copy);
p3.add(paste);
p3.add(cut);

//Add event listening mechanism
copy.addActionListener(this);
paste.addActionListener(this);
cut.addActionListener(this);

// this.copyStr(copy);
jf.add(p1, BorderLayout.NORTH);
jf.add(p2, BorderLayout.CENTER);
jf.add(p3, BorderLayout.SOUTH);
jf.setLocation(400,200);
jf.setSize(600,450);
jf.setResizable(false);
jf.setVisible(true);
}

//event handling
public void actionPerformed(ActionEvent e)
{
if(e.getSource() == copy)
{
String tempText = edit.getSelectedText(); //Drag the mouse to select text
//Create a Transferable that can transfer the specified String.
StringSelection editText =
new StringSelection(tempText);
/**
Sets the current contents of the clipboard to the specified transferable object,
And registers the specified clipboard owner as the owner of the new content.
*/
clipboard.setContents(editText,null);
}else if(e.getSource() == cut)
{
String tempText = edit.getSelectedText();
StringSelection editText =
new StringSelection(tempText);
clipboard.setContents(editText,null);
int start= edit.getSelectionStart();
int end = edit.getSelectionEnd();
showMsg.replaceRange("",start,end); //Delete the selected text from Text1.
}else if(e.getSource() == paste)
{
Transferable contents = clipboard.getContents(this);
DataFlavor flavor= DataFlavor.stringFlavor;
if( contents.isDataFlavorSupported(flavor))
{
try
{
String str;
str = (String)contents.getTransferData(flavor);
showMsg.append(str);
}catch(Exception ex)
{
ex.printStackTrace();
}
}
}
}

public static void main(String[] args)
{
new Demo();
}
}

The code is very simple and easy to use. If you guys have better ideas, please be sure to tell me.