learning java swing 双缓冲和键盘驱动

import javax.swing.*;

import java.awt.*;

import java.awt.event.ActionEvent;

import java.awt.event.InputEvent;

public class BindKeyTest {

    JFrame jf = new JFrame("test keyboard bind");

    JTextArea jta = new JTextArea(,);

    JButton jb = new JButton("发送");

    JTextField jtf = new JTextField();

    public void init(){

        jf.add(jta);

        var jp  = new JPanel();

        jp.add(jtf);

        jp.add(jb);

        jf.add(jp, BorderLayout.SOUTH);

        Action sendMsg = new AbstractAction() {

            @Override

            public void actionPerformed(ActionEvent e) {

                jta.append(jtf.getText() + "\n");

                jtf.setText("");

            }

        };

        jb.addActionListener(sendMsg);

        jtf.getInputMap().put(KeyStroke.getKeyStroke('\n', InputEvent.CTRL_DOWN_MASK), "send");

        jtf.getActionMap().put("send",  sendMsg);

        jf.pack();

        jf.setVisible(true);

    }

    public static void main(String[] args) {

        new BindKeyTest().init();

    }

}

outpu: