java程序,写一个记事本,有查找和替换的功能答:import java.io.*;import java.awt.event.*;import javax.swing.*;public class MainClass extends JFrame implements ActionListener{ int width = 500,height = 400;JPanel panel;JMenuBar bar;JMenu fileMenu,editMenu,helpMenu;JMenuItem 打开O,新建N,保存S,另存A,剪切T,复制C,粘贴P,关于A;...