初步完成的java编写的四则运算！

代码：

import java.awt.*;import java.awt.event.*;import java.util.*;import javax.swing.*;public class arithmetic implements ActionListener {	JFrame f;	JLabel title,title1;	JTextField jfirst1, jfirst2, jfirst3, jfirst4, jfirst5, jfirst6, jfirst7,			jfirst8, jfirst9, jfirst10;// 10道题的分别的第一个数据	JLabel jsymbol1, jsymbol2, jsymbol3, jsymbol4, jsymbol5, jsymbol6,			jsymbol7, jsymbol8, jsymbol9, jsymbol10;// 10道题的分别的符号	JTextField jsecond1, jsecond2, jsecond3, jsecond4, jsecond5, jsecond6,			jsecond7, jsecond8, jsecond9, jsecond10;// 10道题的分别的第二个数据	JTextField janswer1, janswer2, janswer3, janswer4, janswer5, janswer6,			janswer7, janswer8, janswer9, janswer10;// 10道题分别的结果	JLabel jjudge1, jjudge2, jjudge3, jjudge4, jjudge5, jjudge6, jjudge7,			jjudge8, jjudge9, jjudge10;// 判断10道题输入答案的对错	JTextField jjresult1, jjresult2, jjresult3, jjresult4, jjresult5,			jjresult6, jjresult7, jjresult8, jjresult9, jjresult10;// 10道题分别的																	// 正确答案	JButton SubmitBtn;// 提交答案按钮	JButton AddBtn, SubBtn, MulBtn, DivBtn, ExitBtn;// 加法测试，减法测试，乘法测试，除法测试，退出系统	JLabel jtotle, jright, jjright;// 总共题数，提示：“正确题数：”，正确的题数	float first1, first2, first3, first4, first5, first6, first7, first8, first9,			first10;	float second1, second2, second3, second4, second5, second6, second7, second8,			second9, second10;	int flag;	public arithmetic() {		f = new JFrame(" 小学四则运算系统");		f.setBounds(100, 100, 1150, 520);		f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);		Container c = f.getContentPane();		// 添加提示：“请选择”，添加加法测试按钮、减法测试按钮、乘法测试按钮、除法测试按钮、退出测试按钮		JLabel Choose = new JLabel("请选择:");		Choose.setFont(new Font("黑体", Font.BOLD, 18));		AddBtn = new JButton("加法运算");		AddBtn.setFont(new Font("黑体", Font.BOLD, 18));		AddBtn.addActionListener(this);		SubBtn = new JButton("减法运算");		SubBtn.setFont(new Font("黑体", Font.BOLD, 18));		SubBtn.addActionListener(this);		MulBtn = new JButton("乘法运算");		MulBtn.setFont(new Font("黑体", Font.BOLD, 18));		MulBtn.addActionListener(this);		DivBtn = new JButton("除法运算");		DivBtn.setFont(new Font("黑体", Font.BOLD, 18));		DivBtn.addActionListener(this);		ExitBtn = new JButton("退出系统");		ExitBtn.setFont(new Font("黑体", Font.BOLD, 18));		ExitBtn.addActionListener(this);		Box box11 = Box.createVerticalBox();		box11.add(Box.createHorizontalStrut(73));		box11.add(Choose);		box11.add(Box.createVerticalStrut(44));		box11.add(AddBtn);		box11.add(Box.createVerticalStrut(44));		box11.add(SubBtn);		box11.add(Box.createVerticalStrut(44));		box11.add(MulBtn);		box11.add(Box.createVerticalStrut(44));		box11.add(DivBtn);		box11.add(Box.createVerticalStrut(44));		box11.add(ExitBtn);		box11.add(Box.createVerticalStrut(35));		// 添加标签：“您已进入加法测试，现在开始答题："”		title = new JLabel("您好，欢迎进入小学四则运算系统！");		title.setFont(new Font("黑体", Font.BOLD, 18));		Box box = Box.createHorizontalBox();		box.add(Box.createHorizontalGlue());		box.add(title);		box.add(Box.createHorizontalGlue());				//添加提示标签		title1 = new JLabel("注：请在左边栏内选择运算后开始答题，除法运算结果保留两位小数，其余运算保留一位小数。");		title1.setFont(new Font("黑体", Font.BOLD, 14));		Box box12 = Box.createHorizontalBox();		box12.add(Box.createHorizontalGlue());		box12.add(title1);		box12.add(Box.createHorizontalGlue());		// 添加每道题的符号标签		jsymbol1 = new JLabel("?");		jsymbol2 = new JLabel("?");		jsymbol3 = new JLabel("?");		jsymbol4 = new JLabel("?");		jsymbol5 = new JLabel("?");		jsymbol6 = new JLabel("?");		jsymbol7 = new JLabel("?");		jsymbol8 = new JLabel("?");		jsymbol9 = new JLabel("?");		jsymbol10 = new JLabel("?");		// 设置答案对错的标签		jjudge1 = new JLabel("?");		jjudge2 = new JLabel("?");		jjudge3 = new JLabel("?");		jjudge4 = new JLabel("?");		jjudge5 = new JLabel("?");		jjudge6 = new JLabel("?");		jjudge7 = new JLabel("?");		jjudge8 = new JLabel("?");		jjudge9 = new JLabel("?");		jjudge10 = new JLabel("?");		// 为每道题的结果设置为不可更改		jjresult1 = new JTextField(8);		jjresult1.setEditable(false);		jjresult2 = new JTextField(8);		jjresult2.setEditable(false);		jjresult3 = new JTextField(8);		jjresult3.setEditable(false);		jjresult4 = new JTextField(8);		jjresult4.setEditable(false);		jjresult5 = new JTextField(8);		jjresult5.setEditable(false);		jjresult6 = new JTextField(8);		jjresult6.setEditable(false);		jjresult7 = new JTextField(8);		jjresult7.setEditable(false);		jjresult8 = new JTextField(8);		jjresult8.setEditable(false);		jjresult9 = new JTextField(8);		jjresult9.setEditable(false);		jjresult10 = new JTextField(8);		jjresult10.setEditable(false);		// 设置第一个数据和第二个数据为不可见		jfirst1 = new JTextField(6);		jfirst1.setEditable(false);		jfirst2 = new JTextField(6);		jfirst2.setEditable(false);		jsecond1 = new JTextField(6);		jsecond1.setEditable(false);		jsecond2 = new JTextField(6);		jsecond2.setEditable(false);		janswer1 = new JTextField(6);		janswer2 = new JTextField(6);		// 把标签加入盒子box1中		Box box1 = Box.createHorizontalBox();		box1.add(Box.createHorizontalStrut(50));		box1.add(jfirst1);		box1.add(Box.createHorizontalStrut(3));		box1.add(jsymbol1);		box1.add(Box.createHorizontalStrut(3));		box1.add(jsecond1);		box1.add(Box.createHorizontalStrut(5));		box1.add(new JLabel("="));		box1.add(Box.createHorizontalStrut(5));		box1.add(janswer1);		box1.add(Box.createHorizontalStrut(5));		box1.add(new JLabel("对/错："));		box1.add(jjudge1);		box1.add(Box.createHorizontalStrut(20));		box1.add(new JLabel("正确答案："));		box1.add(jjresult1);		box1.add(Box.createHorizontalStrut(73));		box1.add(jfirst2);		box1.add(Box.createHorizontalStrut(3));		box1.add(jsymbol2);		box1.add(Box.createHorizontalStrut(3));		box1.add(jsecond2);		box1.add(Box.createHorizontalStrut(5));		box1.add(new JLabel("="));		box1.add(Box.createHorizontalStrut(5));		box1.add(janswer2);		box1.add(Box.createHorizontalStrut(5));		box1.add(new JLabel("对/错："));		box1.add(jjudge2);		box1.add(Box.createHorizontalStrut(20));		box1.add(new JLabel("正确答案："));		box1.add(jjresult2);		box1.add(Box.createHorizontalStrut(50));		jfirst3 = new JTextField(6);		jfirst3.setEditable(false);		jfirst4 = new JTextField(6);		jfirst4.setEditable(false);		jsecond3 = new JTextField(6);		jsecond3.setEditable(false);		jsecond4 = new JTextField(6);		jsecond4.setEditable(false);		janswer3 = new JTextField(6);		janswer4 = new JTextField(6);		Box box2 = Box.createHorizontalBox();		box2.add(Box.createHorizontalStrut(50));		box2.add(jfirst3);		box2.add(Box.createHorizontalStrut(3));		box2.add(jsymbol3);		box2.add(Box.createHorizontalStrut(3));		box2.add(jsecond3);		box2.add(Box.createHorizontalStrut(5));		box2.add(new JLabel("="));		box2.add(Box.createHorizontalStrut(5));		box2.add(janswer3);		box2.add(Box.createHorizontalStrut(5));		box2.add(new JLabel("对/错："));		box2.add(jjudge3);		box2.add(Box.createHorizontalStrut(20));		box2.add(new JLabel("正确答案："));		box2.add(jjresult3);		box2.add(Box.createHorizontalStrut(73));		box2.add(jfirst4);		box2.add(Box.createHorizontalStrut(3));		box2.add(jsymbol4);		box2.add(Box.createHorizontalStrut(3));		box2.add(jsecond4);		box2.add(Box.createHorizontalStrut(5));		box2.add(new JLabel("="));		box2.add(Box.createHorizontalStrut(5));		box2.add(janswer4);		box2.add(Box.createHorizontalStrut(5));		box2.add(new JLabel("对/错："));		box2.add(jjudge4);		box2.add(Box.createHorizontalStrut(20));		box2.add(new JLabel("正确答案："));		box2.add(jjresult4);		box2.add(Box.createHorizontalStrut(50));		jfirst5 = new JTextField(6);		jfirst5.setEditable(false);		jfirst6 = new JTextField(6);		jfirst6.setEditable(false);		jsecond5 = new JTextField(6);		jsecond5.setEditable(false);		jsecond6 = new JTextField(6);		jsecond6.setEditable(false);		janswer5 = new JTextField(6);		janswer6 = new JTextField(6);		Box box3 = Box.createHorizontalBox();		box3.add(Box.createHorizontalStrut(50));		box3.add(jfirst5);		box3.add(Box.createHorizontalStrut(3));		box3.add(jsymbol5);		box3.add(Box.createHorizontalStrut(3));		box3.add(jsecond5);		box3.add(Box.createHorizontalStrut(5));		box3.add(new JLabel("="));		box3.add(Box.createHorizontalStrut(5));		box3.add(janswer5);		box3.add(Box.createHorizontalStrut(5));		box3.add(new JLabel("对/错："));		box3.add(jjudge5);		box3.add(Box.createHorizontalStrut(20));		box3.add(new JLabel("正确答案："));		box3.add(jjresult5);		box3.add(Box.createHorizontalStrut(73));		box3.add(jfirst6);		box3.add(Box.createHorizontalStrut(3));		box3.add(jsymbol6);		box3.add(Box.createHorizontalStrut(3));		box3.add(jsecond6);		box3.add(Box.createHorizontalStrut(5));		box3.add(new JLabel("="));		box3.add(Box.createHorizontalStrut(5));		box3.add(janswer6);		box3.add(Box.createHorizontalStrut(5));		box3.add(new JLabel("对/错："));		box3.add(jjudge6);		box3.add(Box.createHorizontalStrut(20));		box3.add(new JLabel("正确答案："));		box3.add(jjresult6);		box3.add(Box.createHorizontalStrut(50));		jfirst7 = new JTextField(6);		jfirst7.setEditable(false);		jfirst8 = new JTextField(6);		jfirst8.setEditable(false);		jsecond7 = new JTextField(6);		jsecond7.setEditable(false);		jsecond8 = new JTextField(6);		jsecond8.setEditable(false);		janswer7 = new JTextField(6);		janswer8 = new JTextField(6);		Box box4 = Box.createHorizontalBox();		box4.add(Box.createHorizontalStrut(50));		box4.add(jfirst7);		box4.add(Box.createHorizontalStrut(3));		box4.add(jsymbol7);		box4.add(Box.createHorizontalStrut(3));		box4.add(jsecond7);		box4.add(Box.createHorizontalStrut(5));		box4.add(new JLabel("="));		box4.add(Box.createHorizontalStrut(5));		box4.add(janswer7);		box4.add(Box.createHorizontalStrut(5));		box4.add(new JLabel("对/错："));		box4.add(jjudge7);		box4.add(Box.createHorizontalStrut(20));		box4.add(new JLabel("正确答案："));		box4.add(jjresult7);		box4.add(Box.createHorizontalStrut(73));		box4.add(jfirst8);		box4.add(Box.createHorizontalStrut(3));		box4.add(jsymbol8);		box4.add(Box.createHorizontalStrut(3));		box4.add(jsecond8);		box4.add(Box.createHorizontalStrut(5));		box4.add(new JLabel("="));		box4.add(Box.createHorizontalStrut(5));		box4.add(janswer8);		box4.add(Box.createHorizontalStrut(5));		box4.add(new JLabel("对/错："));		box4.add(jjudge8);		box4.add(Box.createHorizontalStrut(20));		box4.add(new JLabel("正确答案："));		box4.add(jjresult8);		box4.add(Box.createHorizontalStrut(50));		jfirst9 = new JTextField(6);		jfirst9.setEditable(false);		jfirst10 = new JTextField(6);		jfirst10.setEditable(false);		jsecond9 = new JTextField(6);		jsecond9.setEditable(false);		jsecond10 = new JTextField(6);		jsecond10.setEditable(false);		janswer9 = new JTextField(6);		janswer10 = new JTextField(6);		Box box5 = Box.createHorizontalBox();		box5.add(Box.createHorizontalStrut(50));		box5.add(jfirst9);		box5.add(Box.createHorizontalStrut(3));		box5.add(jsymbol9);		box5.add(Box.createHorizontalStrut(3));		box5.add(jsecond9);		box5.add(Box.createHorizontalStrut(5));		box5.add(new JLabel("="));		box5.add(Box.createHorizontalStrut(5));		box5.add(janswer9);		box5.add(Box.createHorizontalStrut(5));		box5.add(new JLabel("对/错："));		box5.add(jjudge9);		box5.add(Box.createHorizontalStrut(20));		box5.add(new JLabel("正确答案："));		box5.add(jjresult9);		box5.add(Box.createHorizontalStrut(73));		box5.add(jfirst10);		box5.add(Box.createHorizontalStrut(3));		box5.add(jsymbol10);		box5.add(Box.createHorizontalStrut(3));		box5.add(jsecond10);		box5.add(Box.createHorizontalStrut(5));		box5.add(new JLabel("="));		box5.add(Box.createHorizontalStrut(5));		box5.add(janswer10);		box5.add(Box.createHorizontalStrut(5));		box5.add(new JLabel("对/错："));		box5.add(jjudge10);		box5.add(Box.createHorizontalStrut(20));		box5.add(new JLabel("正确答案："));		box5.add(jjresult10);		box5.add(Box.createHorizontalStrut(50));		//设置提交答案按钮		SubmitBtn = new JButton("提交答案");		SubmitBtn.setFont(new Font("黑体", Font.BOLD, 18));		SubmitBtn.addActionListener(this);		//添加总题数标签		jtotle = new JLabel("总题数：10 题");		jtotle.setFont(new Font("黑体", Font.BOLD, 18));		//添加答对题数标签		jright = new JLabel("答对题数：");		jright.setFont(new Font("黑体", Font.BOLD, 18));		jjright = new JLabel("0");		jjright.setFont(new Font("黑体", Font.BOLD, 18));		Box box6 = Box.createHorizontalBox();		box6.add(Box.createHorizontalStrut(50));		box6.add(SubmitBtn);		box6.add(Box.createHorizontalStrut(50));		box6.add(jtotle);		box6.add(Box.createHorizontalStrut(50));		box6.add(jright);		box6.add(Box.createHorizontalStrut(20));		box6.add(jjright);		box6.add(Box.createHorizontalStrut(50));		//创建一个容器		Box box7 = Box.createVerticalBox();		box7.add(Box.createVerticalStrut(30));		box7.add(box);		box7.add(Box.createVerticalStrut(30));		box7.add(box12);		box7.add(Box.createVerticalStrut(30));		box7.add(box1);		box7.add(Box.createVerticalStrut(30));		box7.add(box2);		box7.add(Box.createVerticalStrut(30));		box7.add(box3);		box7.add(Box.createVerticalStrut(30));		box7.add(box4);		box7.add(Box.createVerticalStrut(30));		box7.add(box5);		box7.add(Box.createVerticalStrut(30));		box7.add(box6);		box7.add(Box.createVerticalStrut(30));		//创建一个容器		Box box8 = Box.createHorizontalBox();		box8.add(box11);		box8.add(Box.createHorizontalStrut(40));		box8.add(new JSeparator(JSeparator.VERTICAL));		box8.add(box7);		c.add(box8);		f.setVisible(true);	}	public static void main(String args[]) {		new arithmetic();	}	@Override	public void actionPerformed(ActionEvent e) {				/* 加法计算 */		if (e.getSource() == AddBtn) {			flag=1;			jsymbol1.setText("+");			jsymbol2.setText("+");			jsymbol3.setText("+");			jsymbol4.setText("+");			jsymbol5.setText("+");			jsymbol6.setText("+");			jsymbol7.setText("+");			jsymbol8.setText("+");			jsymbol9.setText("+");			jsymbol10.setText("+");			fun();			random();		}		//提交答案并判断		if (e.getSource() == SubmitBtn && flag==1) {			double a1, a2, a3, a4, a5, a6, a7, a8, a9, a10;			int true1 = 0;			// 计算第一道题			String answer1 = null;			a1 = first1 + second1;			answer1 = Double.toString(a1);			String result1 = janswer1.getText();			if (result1.equals(answer1)) {				jjudge1.setText("对");				true1 = true1 + 1;				jjright.setText(Integer.toString(true1));//显示答对题数			} else {				jjudge1.setText("错");				jjresult1.setText(answer1);//显示正确结果			}			// 计算第二道题			String answer2 = null;			a2 = first2 + second2;			answer2 = Double.toString(a2);			String result2 = janswer2.getText();			if (result2.equals(answer2)) {				jjudge2.setText("对");				true1 = true1 + 1;				jjright.setText(Integer.toString(true1));			} else {				jjudge2.setText("错");				jjresult2.setText(answer2);			}			// 计算第三道题			String answer3 = null;			a3 = first3 + second3;			answer3 = Double.toString(a3);			String result3 = janswer3.getText();			if (result3.equals(answer3)) {				jjudge3.setText("对");				true1 = true1 + 1;				jjright.setText(Integer.toString(true1));			} else {				jjudge3.setText("错");				jjresult3.setText(answer3);			}			// 计算第四道题			String answer4 = null;			a4 = first4 + second4;			answer4 = Double.toString(a4);			String result4 = janswer4.getText();			if (result4.equals(answer4)) {				jjudge4.setText("对");				true1 = true1 + 1;				jjright.setText(Integer.toString(true1));			} else {				jjudge4.setText("错");				jjresult4.setText(answer4);			}			// 计算第五道题			String answer5 = null;			a5 = first5 + second5;			answer5 = Double.toString(a5);			String result5 = janswer5.getText();			if (result5.equals(answer5)) {				jjudge5.setText("对");				true1 = true1 + 1;				jjright.setText(Integer.toString(true1));			} else {				jjudge5.setText("错");				jjresult5.setText(answer5);			}			// 计算第六道题			String answer6 = null;			a6 = first6 + second6;			answer6 = Double.toString(a6);			String result6 = janswer6.getText();			if (result6.equals(answer6)) {				jjudge6.setText("对");				true1 = true1 + 1;				jjright.setText(Integer.toString(true1));			} else {				jjudge6.setText("错");				jjresult6.setText(answer6);			}			// 计算第七道题			String answer7 = null;			a7 = first7 + second7;			answer7 = Double.toString(a7);			String result7 = janswer7.getText();			if (result7.equals(answer7)) {				jjudge7.setText("对");				true1 = true1 + 1;				jjright.setText(Integer.toString(true1));			} else {				jjudge7.setText("错");				jjresult7.setText(answer7);			}			// 计算第八道题			String answer8 = null;			a8 = first8 + second8;			answer8 = Double.toString(a8);			String result8 = janswer8.getText();			if (result8.equals(answer8)) {				jjudge8.setText("对");				true1 = true1 + 1;				jjright.setText(Integer.toString(true1));			} else {				jjudge8.setText("错");				jjresult8.setText(answer8);			}			// 计算第九道题			String answer9 = null;			a9 = first9 + second9;			answer9 = Double.toString(a9);			String result9 = janswer9.getText();			if (result9.equals(answer9)) {				jjudge9.setText("对");				true1 = true1 + 1;				jjright.setText(Integer.toString(true1));			} else {				jjudge9.setText("错");				jjresult9.setText(answer9);			}			// 计算第十道题			String answer10 = null;			a10 = first10 + second10;			answer10 = Double.toString(a10);			String result10 = janswer10.getText();			if (result10.equals(answer10)) {				jjudge10.setText("对");				true1 = true1 + 1;				jjright.setText(Integer.toString(true1));			} else {				jjudge10.setText("错");				jjresult10.setText(answer10);			}		}						/* 减法计算 */		else if (e.getSource() == SubBtn) {			flag=2;			jsymbol1.setText("-");			jsymbol2.setText("-");			jsymbol3.setText("-");			jsymbol4.setText("-");			jsymbol5.setText("-");			jsymbol6.setText("-");			jsymbol7.setText("-");			jsymbol8.setText("-");			jsymbol9.setText("-");			jsymbol10.setText("-");			fun();			random();		}		if (e.getSource() == SubmitBtn && flag==2) {			double a1_1, a2_1, a3_1, a4_1, a5_1, a6_1, a7_1, a8_1, a9_1, a10_1;			int true2 = 0;			// 计算第一道题			String answer1_1 = null;			a1_1 = first1 - second1;			answer1_1 = Double.toString(a1_1);			String result1_1 = janswer1.getText();			if (result1_1.equals(answer1_1)) {				jjudge1.setText("对");				true2 = true2 + 1;				jjright.setText(Integer.toString(true2));			} else {				jjudge1.setText("错");				jjresult1.setText(answer1_1);			}			// 计算第二道题			String answer2_1 = null;			a2_1 = first2 - second2;			answer2_1 = Double.toString(a2_1);			String result2_1 = janswer2.getText();			if (result2_1.equals(answer2_1)) {				jjudge2.setText("对");				true2 = true2 + 1;				jjright.setText(Integer.toString(true2));			} else {				jjudge2.setText("错");				jjresult2.setText(answer2_1);			}			// 计算第三道题			String answer3_1 = null;			a3_1 = first3 - second3;			answer3_1 = Double.toString(a3_1);			String result3_1 = janswer3.getText();			if (result3_1.equals(answer3_1)) {				jjudge3.setText("对");				true2 = true2 + 1;				jjright.setText(Integer.toString(true2));			} else {				jjudge3.setText("错");				jjresult3.setText(answer3_1);			}			// 计算第四道题			String answer4_1 = null;			a4_1 = first4 - second4;			answer4_1 = Double.toString(a4_1);			String result4_1 = janswer4.getText();			if (result4_1.equals(answer4_1)) {				jjudge4.setText("对");				true2 = true2 + 1;				jjright.setText(Integer.toString(true2));			} else {				jjudge4.setText("错");				jjresult4.setText(answer4_1);			}			// 计算第五道题			String answer5_1 = null;			a5_1 = first5 - second5;			answer5_1 = Double.toString(a5_1);			String result5_1 = janswer5.getText();			if (result5_1.equals(answer5_1)) {				jjudge5.setText("对");				true2 = true2 + 1;				jjright.setText(Integer.toString(true2));			} else {				jjudge5.setText("错");				jjresult5.setText(answer5_1);			}			// 计算第六道题			String answer6_1 = null;			a6_1 = first6 - second6;			answer6_1 = Double.toString(a6_1);			String result6_1 = janswer6.getText();			if (result6_1.equals(answer6_1)) {				jjudge6.setText("对");				true2 = true2 + 1;				jjright.setText(Integer.toString(true2));			} else {				jjudge6.setText("错");				jjresult6.setText(answer6_1);			}			// 计算第七道题			String answer7_1 = null;			a7_1 = first7 - second7;			answer7_1 = Double.toString(a7_1);			String result7_1 = janswer7.getText();			if (result7_1.equals(answer7_1)) {				jjudge7.setText("对");				true2 = true2 + 1;				jjright.setText(Integer.toString(true2));			} else {				jjudge7.setText("错");				jjresult7.setText(answer7_1);			}			// 计算第八道题			String answer8_1 = null;			a8_1 = first8 - second8;			answer8_1 = Double.toString(a8_1);			String result8_1 = janswer8.getText();			if (result8_1.equals(answer8_1)) {				jjudge8.setText("对");				true2 = true2 + 1;				jjright.setText(Integer.toString(true2));			} else {				jjudge8.setText("错");				jjresult8.setText(answer8_1);			}			// 计算第九道题			String answer9_1 = null;			a9_1 = first9 - second9;			answer9_1 = Double.toString(a9_1);			String result9_1 = janswer9.getText();			if (result9_1.equals(answer9_1)) {				jjudge9.setText("对");				true2 = true2 + 1;				jjright.setText(Integer.toString(true2));			} else {				jjudge9.setText("错");				jjresult9.setText(answer9_1);			}			// 计算第十道题			String answer10_1 = null;			a10_1 = first10 - second10;			answer10_1 = Double.toString(a10_1);			String result10_1 = janswer10.getText();			if (result10_1.equals(answer10_1)) {				jjudge10.setText("对");				true2 = true2 + 1;				jjright.setText(Integer.toString(true2));			} else {				jjudge10.setText("错");				jjresult10.setText(answer10_1);			}		}						/* 乘法计算 */		else if (e.getSource() == MulBtn) {			flag=3;			jsymbol1.setText("*");			jsymbol2.setText("*");			jsymbol3.setText("*");			jsymbol4.setText("*");			jsymbol5.setText("*");			jsymbol6.setText("*");			jsymbol7.setText("*");			jsymbol8.setText("*");			jsymbol9.setText("*");			jsymbol10.setText("*");			fun();			random();		}		if (e.getSource() == SubmitBtn && flag==3) {			double a1_2, a2_2, a3_2, a4_2, a5_2, a6_2, a7_2, a8_2, a9_2, a10_2;			int true3 = 0;			// 计算第一道题			String answer1_2 = null;			a1_2 = first1 * second1;			answer1_2 = Double.toString(a1_2);			String result1_2 = janswer1.getText();			if (result1_2.equals(answer1_2)) {				jjudge1.setText("对");				true3 = true3 + 1;				jjright.setText(Integer.toString(true3));			} else {				jjudge1.setText("错");				jjresult1.setText(answer1_2);			}			// 计算第二道题			String answer2_2 = null;			a2_2 = first2 * second2;			answer2_2 = Double.toString(a2_2);			String result2_2 = janswer2.getText();			if (result2_2.equals(answer2_2)) {				jjudge2.setText("对");				true3 = true3 + 1;				jjright.setText(Integer.toString(true3));			} else {				jjudge2.setText("错");				jjresult2.setText(answer2_2);			}			// 计算第三道题			String answer3_2 = null;			a3_2 = first3 * second3;			answer3_2 = Double.toString(a3_2);			String result3_2 = janswer3.getText();			if (result3_2.equals(answer3_2)) {				jjudge3.setText("对");				true3 = true3 + 1;				jjright.setText(Integer.toString(true3));			} else {				jjudge3.setText("错");				jjresult3.setText(answer3_2);			}			// 计算第四道题			String answer4_2 = null;			a4_2 = first4 * second4;			answer4_2 = Double.toString(a4_2);			String result4_2 = janswer4.getText();			if (result4_2.equals(answer4_2)) {				jjudge4.setText("对");				true3 = true3 + 1;				jjright.setText(Integer.toString(true3));			} else {				jjudge4.setText("错");				jjresult4.setText(answer4_2);			}			// 计算第五道题			String answer5_2 = null;			a5_2 = first5 * second5;			answer5_2 = Double.toString(a5_2);			String result5_2 = janswer5.getText();			if (result5_2.equals(answer5_2)) {				jjudge5.setText("对");				true3 = true3 + 1;				jjright.setText(Integer.toString(true3));			} else {				jjudge5.setText("错");				jjresult5.setText(answer5_2);			}			// 计算第六道题			String answer6_2 = null;			a6_2 = first6 * second6;			answer6_2 = Double.toString(a6_2);			String result6_2 = janswer6.getText();			if (result6_2.equals(answer6_2)) {				jjudge6.setText("对");				true3 = true3 + 1;				jjright.setText(Integer.toString(true3));			} else {				jjudge6.setText("错");				jjresult6.setText(answer6_2);			}			// 计算第七道题			String answer7_2 = null;			a7_2 = first7 * second7;			answer7_2 = Double.toString(a7_2);			String result7_2 = janswer7.getText();			if (result7_2.equals(answer7_2)) {				jjudge7.setText("对");				true3 = true3 + 1;				jjright.setText(Integer.toString(true3));			} else {				jjudge7.setText("错");				jjresult7.setText(answer7_2);			}			// 计算第八道题			String answer8_2 = null;			a8_2 = first8 * second8;			answer8_2 = Double.toString(a8_2);			String result8_2 = janswer8.getText();			if (result8_2.equals(answer8_2)) {				jjudge8.setText("对");				true3 = true3 + 1;				jjright.setText(Integer.toString(true3));			} else {				jjudge8.setText("错");				jjresult8.setText(answer8_2);			}			// 计算第九道题			String answer9_2 = null;			a9_2 = first9 * second9;			answer9_2 = Double.toString(a9_2);			String result9_2 = janswer9.getText();			if (result9_2.equals(answer9_2)) {				jjudge9.setText("对");				true3 = true3 + 1;				jjright.setText(Integer.toString(true3));			} else {				jjudge9.setText("错");				jjresult9.setText(answer9_2);			}			// 计算第十道题			String answer10_2 = null;			a10_2 = first10 * second10;			answer10_2 = Double.toString(a10_2);			String result10_2 = janswer10.getText();			if (result10_2.equals(answer10_2)) {				jjudge10.setText("对");				true3 = true3 + 1;				jjright.setText(Integer.toString(true3));			} else {				jjudge10.setText("错");				jjresult10.setText(answer10_2);			}		}						/* 除法计算 */		else if (e.getSource() == DivBtn) {			flag=4;			jsymbol1.setText("/");			jsymbol2.setText("/");			jsymbol3.setText("/");			jsymbol4.setText("/");			jsymbol5.setText("/");			jsymbol6.setText("/");			jsymbol7.setText("/");			jsymbol8.setText("/");			jsymbol9.setText("/");			jsymbol10.setText("/");			fun();			random();		}		if (e.getSource() == SubmitBtn && flag==4) {			double a1_3, a2_3, a3_3, a4_3, a5_3, a6_3, a7_3, a8_3, a9_3, a10_3;			int true4 = 0;			// 计算第一道题			String answer1_3 = null;			if(second1==0){				do{					random();				}while(second1!=0);			}//除数为0时的操作			a1_3 = first1 / second1;            answer1_3 = String.format("%.2f", a1_3);//除法结果保留小数点后两位			String result1_3 = janswer1.getText();			if (result1_3.equals(answer1_3)) {//判断输入结果与正确结果是否相等				jjudge1.setText("对");				true4 = true4 + 1;				jjright.setText(Integer.toString(true4));			} else {				jjudge1.setText("错");				jjresult1.setText(answer1_3);			}			// 计算第二道题			String answer2_3 = null;			if(second1==0){				do{					random();				}while(second1!=0);			}			a2_3 = first2 / second2;            answer2_3 = String.format("%.2f", a2_3);			String result2_3 = janswer2.getText();			if (result2_3.equals(answer2_3)) {				jjudge2.setText("对");				true4 = true4 + 1;				jjright.setText(Integer.toString(true4));			} else {				jjudge2.setText("错");				jjresult2.setText(answer2_3);			}			// 计算第三道题			String answer3_3 = null;			if(second1==0){				do{					random();				}while(second1!=0);			}			a3_3 = first3 / second3;            answer3_3 = String.format("%.2f", a3_3);			String result3_3 = janswer3.getText();			if (result3_3.equals(answer3_3)) {				jjudge3.setText("对");				true4 = true4 + 1;				jjright.setText(Integer.toString(true4));			} else {				jjudge3.setText("错");				jjresult3.setText(answer3_3);			}			// 计算第四道题			String answer4_3 = null;			if(second1==0){				do{					random();				}while(second1!=0);			}			a4_3 = first4 / second4;            answer4_3 = String.format("%.2f", a4_3);			String result4_3 = janswer4.getText();			if (result4_3.equals(answer4_3)) {				jjudge4.setText("对");				true4 = true4 + 1;				jjright.setText(Integer.toString(true4));			} else {				jjudge4.setText("错");				jjresult4.setText(answer4_3);			}			// 计算第五道题			String answer5_3 = null;			if(second1==0){				do{					random();				}while(second1!=0);			}			a5_3 = first5 / second5;            answer5_3 = String.format("%.2f", a5_3);			String result5_3 = janswer5.getText();			if (result5_3.equals(answer5_3)) {				jjudge5.setText("对");				true4 = true4 + 1;				jjright.setText(Integer.toString(true4));			} else {				jjudge5.setText("错");				jjresult5.setText(answer5_3);			}			// 计算第六道题			String answer6_3 = null;			if(second1==0){				do{					random();				}while(second1!=0);			}			a6_3 = first6 / second6;            answer6_3 = String.format("%.2f", a6_3);			String result6_3 = janswer6.getText();			if (result6_3.equals(answer6_3)) {				jjudge6.setText("对");				true4 = true4 + 1;				jjright.setText(Integer.toString(true4));			} else {				jjudge6.setText("错");				jjresult6.setText(answer6_3);			}			// 计算第七道题			String answer7_3 = null;			if(second1==0){				do{					random();				}while(second1!=0);			}			a7_3 = first7 / second7;            answer7_3 = String.format("%.2f", a7_3);			String result7_3 = janswer7.getText();			if (result7_3.equals(answer7_3)) {				jjudge7.setText("对");				true4 = true4 + 1;				jjright.setText(Integer.toString(true4));			} else {				jjudge7.setText("错");				jjresult7.setText(answer7_3);			}			// 计算第八道题			String answer8_3 = null;			if(second1==0){				do{					random();				}while(second1!=0);			}			a8_3 = first8 / second8;            answer8_3 = String.format("%.2f", a8_3);			String result8_3 = janswer8.getText();			if (result8_3.equals(answer8_3)) {				jjudge8.setText("对");				true4 = true4 + 1;				jjright.setText(Integer.toString(true4));			} else {				jjudge8.setText("错");				jjresult8.setText(answer8_3);			}			// 计算第九道题			String answer9_3 = null;			if(second1==0){				do{					random();				}while(second1!=0);			}			a9_3 = first9 / second9;            answer9_3 = String.format("%.2f", a9_3);			String result9_3 = janswer9.getText();			if (result9_3.equals(answer9_3)) {				jjudge9.setText("对");				true4 = true4 + 1;				jjright.setText(Integer.toString(true4));			} else {				jjudge9.setText("错");				jjresult9.setText(answer9_3);			}			// 计算第十道题			String answer10_3 = null;			if(second1==0){				do{					random();				}while(second1!=0);			}			a10_3 = first10 / second10;            answer10_3 = String.format("%.2f", a10_3);			String result10_3 = janswer10.getText();			if (result10_3.equals(answer10_3)) {				jjudge10.setText("对");				true4 = true4 + 1;				jjright.setText(Integer.toString(true4));			} else {				jjudge10.setText("错");				jjresult10.setText(answer10_3);			}		}		else if (e.getSource() == ExitBtn) {			System.exit(0);		}	}		/*将十个题分别的第一个数和第二个数置为空，将答对题数置为“？”*/	public void fun(){		janswer1.setText("");		janswer2.setText("");		janswer3.setText("");		janswer4.setText("");		janswer5.setText("");		janswer6.setText("");		janswer7.setText("");		janswer8.setText("");		janswer9.setText("");		janswer10.setText("");		jjresult1.setText("");		jjresult2.setText("");		jjresult3.setText("");		jjresult4.setText("");		jjresult5.setText("");		jjresult6.setText("");		jjresult7.setText("");		jjresult8.setText("");		jjresult9.setText("");		jjresult10.setText("");		jjright.setText("0");	}		/*产生十道题分别第一个数和第二个数的随机数*/	public void random(){		Random rand = new Random();		first1 = rand.nextInt(200);		first1 = first1 - 100;		second1 = rand.nextInt(200);		second1 = second1 - 100;		if (first1 < 0) {			String f1 = Float.toString(first1);			jfirst1.setText("(" + f1 + ")");		} else {			String f1 = Float.toString(first1);			jfirst1.setText(f1);		}		if (second1 < 0) {			String s1 = Float.toString(second1);			jsecond1.setText("(" + s1 + ")");		} else {			String s1 = Float.toString(second1);			jsecond1.setText(s1);		}		first2 = rand.nextInt(200);		first2 = first2 - 100;		second2 = rand.nextInt(200);		second2 = second2 - 100;		if (first2 < 0) {			String f2 = Float.toString(first2);			jfirst2.setText("(" + f2 + ")");		} else {			String f2 = Float.toString(first2);			jfirst2.setText(f2);		}		if (second2 < 0) {			String s2 = Float.toString(second2);			jsecond2.setText("(" + s2 + ")");		} else {			String s2 = Float.toString(second2);			jsecond2.setText(s2);		}		first3 = rand.nextInt(200);		first3 = first3 - 100;		second3 = rand.nextInt(200);		second3 = second3 - 100;		if (first3 < 0) {			String f3 = Float.toString(first3);			jfirst3.setText("(" + f3 + ")");		} else {			String f3 = Float.toString(first3);			jfirst3.setText(f3);		}		if (second3 < 0) {			String s3 = Float.toString(second3);			jsecond3.setText("(" + s3 + ")");		} else {			String s3 = Float.toString(second3);			jsecond3.setText(s3);		}		first4 = rand.nextInt(200);		first4 = first4 - 100;		second4 = rand.nextInt(200);		second4 = second4 - 100;		if (first4 < 0) {			String f4 = Float.toString(first4);			jfirst4.setText("(" + f4 + ")");		} else {			String f4 = Float.toString(first4);			jfirst4.setText(f4);		}		if (second4 < 0) {			String s4 = Float.toString(second4);			jsecond4.setText("(" + s4 + ")");		} else {			String s4 = Float.toString(second4);			jsecond4.setText(s4);		}		first5 = rand.nextInt(200);		first5 = first5 - 100;		second5 = rand.nextInt(200);		second5 = second5 - 100;		if (first5 < 0) {			String f5 = Float.toString(first5);			jfirst5.setText("(" + f5 + ")");		} else {			String f5 = Float.toString(first5);			jfirst5.setText(f5);		}		if (second5 < 0) {			String s5 = Float.toString(second5);			jsecond5.setText("(" + s5 + ")");		} else {			String s5 = Float.toString(second5);			jsecond5.setText(s5);		}		first6 = rand.nextInt(200);		first6 = first6 - 100;		second6 = rand.nextInt(200);		second6 = second6 - 100;		if (first6 < 0) {			String f6 = Float.toString(first6);			jfirst6.setText("(" + f6 + ")");		} else {			String f6 = Float.toString(first6);			jfirst6.setText(f6);		}		if (second6 < 0) {			String s6 = Float.toString(second6);			jsecond6.setText("(" + s6 + ")");		} else {			String s6 = Float.toString(second6);			jsecond6.setText(s6);		}		first7 = rand.nextInt(200);		first7 = first7 - 100;		second7 = rand.nextInt(200);		second7 = second7 - 100;		if (first7 < 0) {			String f7 = Float.toString(first7);			jfirst7.setText("(" + f7 + ")");		} else {			String f7 = Float.toString(first7);			jfirst7.setText(f7);		}		if (second7 < 0) {			String s7 = Float.toString(second7);			jsecond7.setText("(" + s7 + ")");		} else {			String s7 = Float.toString(second7);			jsecond7.setText(s7);		}		first8 = rand.nextInt(200);		first8 = first8 - 100;		second8 = rand.nextInt(200);		second8 = second8 - 100;		if (first8 < 0) {			String f8 = Float.toString(first8);			jfirst8.setText("(" + f8 + ")");		} else {			String f8 = Float.toString(first8);			jfirst8.setText(f8);		}		if (second8 < 0) {			String s8 = Float.toString(second8);			jsecond8.setText("(" + s8 + ")");		} else {			String s8 = Float.toString(second8);			jsecond8.setText(s8);		}		first9 = rand.nextInt(200);		first9 = first9 - 100;		second9 = rand.nextInt(200);		second9 = second9 - 100;		if (first9 < 0) {			String f9 = Float.toString(first9);			jfirst9.setText("(" + f9 + ")");		} else {			String f9 = Float.toString(first9);			jfirst9.setText(f9);		}		if (second9 < 0) {			String s9 = Float.toString(second9);			jsecond9.setText("(" + s9 + ")");		} else {			String s9 = Float.toString(second9);			jsecond9.setText(s9);		}		first10 = rand.nextInt(200);		first10 = first10 - 100;		second10 = rand.nextInt(200);		second10 = second10 - 100;		if (first10 < 0) {			String f10 = Float.toString(first10);			jfirst10.setText("(" + f10 + ")");		} else {			String f10 = Float.toString(first10);			jfirst10.setText(f10);		}		if (second10 < 0) {			String s10 = Float.toString(second10);			jsecond10.setText("(" + s10 + ")");		} else {			String s10 = Float.toString(second10);			jsecond10.setText(s10);		}	}}

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