import javax.swing.JFrame;

import javax.swing.JButton;

import javax.swing.JOptionPane;

import javax.swing.SwingUtilities;

import java.awt.event.ActionListener;

import java.awt.event.ActionEvent;

public class Sample extends JFrame {

public Sample() {

super();

this.setTitle("HelloApp");

this.getContentPane().setLayout(null);

this.setBounds(250, 250, 400, 400);

this.add(makeButton());

this.add(makeButton2());

this.add(makeButton3());

this.add(makeButton4());

this.setVisible(true);

this.setResizable(false);

this.setDefaultCloseOperation(EXIT_ON_CLOSE);

}

private JButton makeButton() {

final JButton b = new JButton();

b.setText("utf-16 hex)");

b.setBounds(40, 40, 100, 40);

b.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

JOptionPane.showMessageDialog(b, "0xD83D 0xDE00 ");

}

});

return b;

}

private JButton makeButton2() {

final JButton b2 = new JButton();

b2.setText("utf-16 bin");

b2.setBounds(40, 90, 100, 40);

b2.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

JOptionPane.showMessageDialog(b2, "11011000 00111101 11011110 00000000");

}

});

return b2;

}

private JButton makeButton3(){

final JButton b3 = new JButton();

b3.setText("utf- 8 hex");

b3.setBounds(40, 140, 100, 40);

b3.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

JOptionPane.showMessageDialog(b3, "0xF0 0x9F 0x98 0x80");

}

});

return b3;

}

private JButton makeButton4(){

final JButton b4 = new JButton();

b4.setText("utf- 8 bin");

b4.setBounds(40, 190, 100, 40);

b4.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

JOptionPane.showMessageDialog(b4, "11110000 10011111 10011000 10000000");

}

});

return b4;

}

public static void main(String[] args) {

// Swing calls must be run by the event dispatching thread.

try{

SwingUtilities.invokeAndWait(() -> new Sample());

}

catch( Exception e ){

System.out.println("error");

}

}

}