displayclock.java

此源码为机械工业出版社出版的《Java语言程序设计》第三版所配套的书中所有源代码。

// DisplayClock.java: Display a clock in a panel
import java.awt.*;
import javax.swing.*;

public class DisplayClock extends JFrame
{
  // Main method with three auguments:
  // args[0]: hour
  // args[1]: minute
  // args[2]: second
  public static void main(String[] args)
  {
    // Declare hour, minute, and second values
    int hour = 0;
    int minute = 0;
    int second = 0;

    // Check usage and get hour, minute, second
    if (args.length > 3)
    {
      System.out.println(
        "Usage: java DisplayClock hour minute second");
      System.exit(0);
    }
    else if (args.length == 3)
    {
      hour = new Integer(args[0]).intValue();
      minute = new Integer(args[1]).intValue();
      second = new Integer(args[2]).intValue();
    }
    else if (args.length == 2)
    {
      hour = new Integer(args[0]).intValue();
      minute = new Integer(args[1]).intValue();
    }
    else if (args.length == 1)
    {
      hour = new Integer(args[0]).intValue();
    }

    // Create a frame to hold the clock
    DisplayClock frame = new DisplayClock();
    frame.setTitle("Display Clock");
    frame.getContentPane().add(new DrawClock(hour, minute, second));
    // frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setSize(300, 350);
    frame.setVisible(true);
  }
}