import java.awt.*; 
import java.util.*; 
 
import javax.swing.*; 
public class SleepMethodTest extends JFrame { 
  /** 
   * 
   */ 
  private static final long serialVersionUID = 1L; 
  private Thread t; 
  // 定義顏色數(shù)組 
  private static Color[] color = { Color.BLACK, Color.BLUE, Color.CYAN, 
      Color.GREEN, Color.ORANGE, Color.YELLOW, Color.RED, 
      Color.PINK, Color.LIGHT_GRAY }; 
  private static final Random rand = new Random();// 創(chuàng)建隨機(jī)對(duì)象 
   
  private static Color getC() {// 獲取隨機(jī)顏色值的方法 
    return color[rand.nextInt(color.length)]; 
  } 
   
  public SleepMethodTest() { 
    t = new Thread(new Runnable() {// 創(chuàng)建匿名線程對(duì)象 
      int x = 30;// 定義初始坐標(biāo) 
      int y = 50; 
       
      public void run() {// 覆蓋線程接口方法 
        while (true) {// 無限循環(huán) 
          try { 
            Thread.sleep(100);// 線程休眠0.1秒 
          } catch (InterruptedException e) { 
            e.printStackTrace(); 
          } 
          // 獲取組件繪圖上下文對(duì)象 
          Graphics graphics = getGraphics(); 
          graphics.setColor(getC());// 設(shè)置繪圖顏色 
          // 繪制直線并遞增垂直坐標(biāo) 
          graphics.drawLine(x, y, 100, y++); 
          if (y >= 80) { 
            y = 50; 
          } 
        } 
      } 
    }); 
    t.start();// 啟動(dòng)線程 
  } 
   
  public static void main(String[] args) { 
    init(new SleepMethodTest(), 100, 100); 
  } 
  // 初始化程序界面的方法 
  public static void init(JFrame frame, int width, int height) { 
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
    frame.setSize(width, height); 
    frame.setVisible(true); 
  } 
}