Java多线程计算阶乘

import java.awt.BorderLayout;
import java.awt.ScrollPane;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.Scrollable;
import alg.Calculate;
public class ThreadUI {
	private JTextField textField;
	private JTextArea consoleArea;
	private Calculate cal;
	private Thread thread;
	public ThreadUI() {
		JFrame frame = new JFrame("阶乘计算所用时间统计");
		frame.setSize(500, 500);
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		// 北侧,加操作栏
		frame.setLayout(new BorderLayout());
		JPanel northPan = new JPanel();
		JLabel label = new JLabel("请输入n的值:");
		textField = new JTextField(5);
		JButton stratBtn = new JButton("开始计算");
		stratAction(stratBtn);
		JButton pauseBtn = new JButton("暂停计算");
		pauseAction(pauseBtn);
		JButton stopBtn = new JButton("停止计算");
		stopAction(stopBtn);
		northPan.add(label);
		northPan.add(textField);
		northPan.add(stratBtn);
		northPan.add(pauseBtn);
		northPan.add(stopBtn);
		frame.add(northPan, BorderLayout.NORTH);
		// 中间，记录计算过程与结果
		consoleArea = new JTextArea();
		JScrollPane scrollPane = new JScrollPane(consoleArea);
		frame.add(scrollPane, BorderLayout.CENTER);
		frame.setVisible(true);
	}
	// 停止计算的事件
	private void stopAction(JButton stopBtn) {
		stopBtn.addActionListener((e) -> {
			 cal.stop();
			//thread.stop();
		});
	}
	// 暂停计算的事件
	private  void  pauseAction(JButton pauseBtn) {
		pauseBtn.addActionListener((e) -> {
			String pauseText = pauseBtn.getText();
			if (pauseText.equals("暂停计算")) {
				 cal.suspend();
				//thread.suspend();
				pauseBtn.setText("继续计算");
			} else {
				 cal.resume();
				//thread.resume();
				pauseBtn.setText("暂停计算");
			}
		});
	}
	// 开始计算的事件
	private void stratAction(JButton button) {
		button.addActionListener((e) -> {
			consoleArea.setText(null);
			String input = textField.getText();
			if(input==null || input.equals(""))
			{
				consoleArea.setText("请先输入您要计算的阶乘值");
				return;
			}
			int n = Integer.valueOf(input);
			cal = new Calculate(n, (content) -> {
				consoleArea.append(content + "\n");
			});
//			thread = new Thread(cal);
//			thread.start();
			cal.start();
		});
	}
	public static void main(String[] args) {
		new ThreadUI();
	}
}

import java.math.BigInteger;
import ui.Logable;
public class Calculate extends Thread /*implements Runnable*/{
	private int n;
	private Logable logable;
	public Calculate(int n,Logable log) {
		this.n=n;
		this.logable=log;
	}
	private void caculate() throws InterruptedException {
		BigInteger res=BigInteger.valueOf(1);
		BigInteger sum=BigInteger.valueOf(0);
		StringBuilder sb = new StringBuilder();
		for(int i=1;i<=n;i++) {	
			res=res.multiply(BigInteger.valueOf(i));
			sum=sum.add(res);
			sb.append((i==1 ? "":"+")+i+"!");
			logable.log(sb.toString()+"="+sum);
			try {
				Thread.sleep((int)(Math.random()*500+500));
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		}
	}
	@Override
	public void run() {
		try {
			caculate();
		} catch (InterruptedException e) {
			e.printStackTrace();
		}
		}
}