线程的正弦函数

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class SinTest extends JFrame {
	double a=100;
	double b=100.0;
	////double c=10.0;
	public SinTest() {
		getContentPane().setLayout(new BorderLayout());
		displayPanel.setBackground(Color.gray);
		drawPanel=new DrawPanel(this);
		getContentPane().add(drawPanel,"Center");
		pack();
		}
	public static void main(String args[]){
		SinTest st=new SinTest();
	
		st.setLocation(200,200);
		st.setVisible(true);
		st.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		}
	public double getA(){
		return a;
		}
	double f(double x,double c) {
		return (Math.sin(x/a+c) * b+getSize().height / 2);
	
	}


	public String getAppletInfo() {
		return "绘制正弦曲线";
		}

	private DrawPanel drawPanel;
	private JPanel displayPanel=new JPanel();

	}

class DrawPanel extends JPanel implements Runnable,MouseListener{
////***************************************
	double c;
	Thread thread;
	boolean isStopped;
	public DrawPanel(SinTest owner) {
		graApp=owner;
	//********************************
		c=0.0;
		this.setPreferredSize(new Dimension(800,300));
		this.addMouseListener(this);
		(thread=new Thread(this)).start();
		}

	public void paint(Graphics g) {
		graApp.setTitle("C:"+c);
		g.clearRect(0,0,getSize().width,getSize().height);
		g.setColor(Color.red);
		for (int x = 0 ; x < getSize().width ; x++) {
		g.drawLine(x, (int)(graApp.f(x,c)), x + 1, (int)(graApp.f(x + 1,c)));
		}
	}

	public void run() {
		while(true){
		repaint();
		if(!isStopped)
		if((c+=.1)>2*Math.PI*graApp.getA())c=0;
		
		try {
		thread.sleep(100);
		} catch (InterruptedException ex) {
		ex.printStackTrace();
				}
			}
		}

	public void mouseClicked(MouseEvent e) {
	
		}

	public void mousePressed(MouseEvent e) {
		}

	public void mouseReleased(MouseEvent e) {
		isStopped=!isStopped;
	
		}

	public void mouseEntered(MouseEvent e) {
		}

	public void mouseExited(MouseEvent e) {
		}

	SinTest graApp;
	}