serialsample.java

Java程序设计实用教程源代码 本书源代码按章分别放置在不同的文件夹中,所有程序均在JDK1.6环境下编译运行正常,除了第13章需要建立ODBC数据源之外,其他程序只要有Java运行环境即可直接运行

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.*;
import java.io.*;
public class SerialSample
    extends JFrame {
  private JPanel contentPane;
  private JPanel jPanel1 = new JPanel();
  private BorderLayout borderLayout1 = new BorderLayout();
  private GridLayout gridLayout1 = new GridLayout(1, 3, 1, 1);
  private JButton jButton1 = new JButton();
  private JButton jButton2 = new JButton();
  private JButton jButton3 = new JButton();
  private DrawPicture area = new DrawPicture();
  ArrayList picture = new ArrayList();
  public SerialSample() {
    enableEvents(AWTEvent.WINDOW_EVENT_MASK);
    try {
      jbInit();
    }
    catch (Exception e) {
      e.printStackTrace();
    }
  }

  private void jbInit() throws Exception {
    contentPane = (JPanel)this.getContentPane();
    jButton1.setRolloverEnabled(true);
    jButton1.setText("Save");
    jButton1.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(ActionEvent e) {
        jButton1_actionPerformed(e);
      }
    });
    contentPane.setLayout(borderLayout1);
    this.setSize(new Dimension(400, 200));
    this.setTitle("Serial Sample");
    jButton2.setText("Clear");
    jButton2.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(ActionEvent e) {
        jButton2_actionPerformed(e);
      }
    });
    jButton3.setRolloverEnabled(true);
    jButton3.setText("Load");
    jButton3.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(ActionEvent e) {
        jButton3_actionPerformed(e);
      }
    });
    area.addMouseListener(draw);
    jPanel1.setLayout(gridLayout1);
    jPanel1.add("b1", jButton1);
    jPanel1.add("b2", jButton2);
    jPanel1.add("b3", jButton3);
    contentPane.add(jPanel1, BorderLayout.NORTH);
    contentPane.add(area, BorderLayout.CENTER);
  }

  void jButton1_actionPerformed(ActionEvent e) {
    FileDialog fd = new FileDialog(this, "另存为", FileDialog.SAVE);
    fd.show();
    String fileName = fd.getFile();
    try {
      ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream(
          fileName));
      out.writeObject(picture);
      out.flush();
      out.close();
    }
    catch (Exception ex) {
    }
  }

  void jButton2_actionPerformed(ActionEvent e) {
    picture = new ArrayList();
    repaint();
  }

  void jButton3_actionPerformed(ActionEvent e) {
    FileDialog fd = new FileDialog(this, "打开文件", FileDialog.LOAD);
    fd.setVisible(true);
    String fileName = fd.getFile();
    try {
      ObjectInputStream in = new ObjectInputStream(new FileInputStream(fileName));
      picture = (ArrayList) (in.readObject());
      in.close();
      repaint();
    }
    catch (Exception ex) {
    }
  }

  protected void processWindowEvent(WindowEvent e) {
    super.processWindowEvent(e);
    if (e.getID() == WindowEvent.WINDOW_CLOSING) {
      System.exit(0);
    }
  }

  public static void main(String[] args) {
    SerialSample frame1 = new SerialSample();
    frame1.setSize(400, 400);
    frame1.setVisible(true);
  }

  MouseAdapter draw = new MouseAdapter() {
    public void mousePressed(MouseEvent e) {
      Point p = new Point(e.getX(), e.getY());
      picture.add(p);
      repaint();
    }
  };
  class DrawPicture
      extends JTextArea {
    DrawPicture() {
      super("", 15, 20);
      repaint();
    }

    public void paintComponent(Graphics g) {
      super.paintComponent(g);
      g.setColor(Color.red);
      int i = 0;
      while (i < picture.size()) {
        Point p0 = (Point) (picture.get(i++));
        int x = p0.x;
        int y = p0.y;
        g.drawOval(x, y, 50, 50);
      }
    }
  }
}