package note;

import java.awt.EventQueue;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.io.BufferedReader;

import java.io.BufferedWriter;

import java.io.File;

import java.io.FileReader;

import java.io.FileWriter;

import java.io.IOException;

import javax.swing.JFrame;

import java.awt.BorderLayout;

import javax.swing.JMenuBar;

import javax.swing.JMenu;

import javax.swing.JMenuItem;

import javax.swing.JSeparator;

import javax.swing.JTextArea;

import java.awt.Font;

/**记事本的图形用户界面应用程序 过滤

 * @author 李祖林

 *2017-6-23

 */

public class Note3 implements ActionListener{

    private JFrame frame;

    JMenuItem New,Open,Save,Close;

    JTextArea textArea;

    File fileName = new File("D://file.txt");

    public static void main(String[] args) {

        EventQueue.invokeLater(new Runnable() {

            public void run() {

                try {

                    Note3 window = new Note3();

                    window.frame.setVisible(true);

                } catch (Exception e) {

                    e.printStackTrace();

                }

            }

        });

    }

    public Note3() {

        frame = new JFrame();

        frame.setBounds(100, 100, 725, 392);

        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        frame.getContentPane().setLayout(new BorderLayout(0, 0));

        textArea = new JTextArea();

        textArea.setFont(new Font("华文中宋", Font.BOLD, 17));

        frame.getContentPane().add(textArea, BorderLayout.CENTER);

        JMenuBar menuBar = new JMenuBar();

        frame.setJMenuBar(menuBar);

        JMenu menu = new JMenu("\u6587\u4EF6");

        menuBar.add(menu);

        New = new JMenuItem("\u65B0\u5EFA");

        menu.add(New);New.addActionListener(this);

        Open = new JMenuItem("\u6253\u5F00");

        menu.add(Open);Open.addActionListener(this);

        Save = new JMenuItem("\u4FDD\u5B58");

        menu.add(Save);Save.addActionListener(this);

        JSeparator separator = new JSeparator();

        menu.add(separator);

        Close = new JMenuItem("\u9000\u51FA");

        menu.add(Close);Close.addActionListener(this);

        JMenu menu_1 = new JMenu("\u7F16\u8F91");

        menuBar.add(menu_1);

        JMenuItem menuItem_4 = new JMenuItem("\u590D\u5236");

        menu_1.add(menuItem_4);

        JMenuItem menuItem_5 = new JMenuItem("\u526A\u5207");

        menu_1.add(menuItem_5);

        JMenuItem menuItem_6 = new JMenuItem("\u7C98\u8D34");

        menu_1.add(menuItem_6);

    }

    public void actionPerformed(ActionEvent e) {

        if (e.getSource() == Close) {

            System.exit(0);

        } else if (e.getSource() == New) {

            textArea.setText("");

        } else if (e.getSource() == Save) {

            saveFile();

        } else if (e.getSource() == Open) {

            textArea.setText("");

            openFile();

        }

    }

    public void saveFile(){

        try {

            BufferedWriter bWriter = new BufferedWriter(new FileWriter(fileName));

                                                            //打开写入流

            String text = textArea.getText();                //获取文本框内容

            char[] ch = new char[1024];                        //字符串->>字符数组

            ch = text.toCharArray();

            int tmp;

            for(int i = 0;i < ch.length;i++){

                tmp = (int)ch[i];                            //字符->ASCII值

                if(tmp>='A'&&tmp<='Z'){                        //过滤

                    tmp += 32;

                }

                ch[i] = (char)tmp;                            //ASCII值->字符

            }

            text = String.valueOf(ch);                        //字符数组->>字符串

            bWriter.write(text);                            //写入

            bWriter.close();

        } catch (IOException e) {

            System.err.println("保存文件发生错误！");

            e.printStackTrace();                            //打印轨迹

        }

    }

    public void openFile(){

        try {

            BufferedReader bReader = new BufferedReader(new FileReader(fileName));

            String text;

            while((text = bReader.readLine())!=null){

                textArea.append(text+"\n");

            }

            bReader.close();

        } catch (IOException e) {

            System.err.println("打开文件发生错误！");

            e.printStackTrace();

        }

    }

}