《面向对象程序设计（java）》第十八周学习总结
第一部分：理论知识学习部分
第二部分：实验部分
实验名称：实验十八 总复习
1、实验目的与要求
(1) 综合掌握java基本程序结构；
(2) 综合掌握java面向对象程序设计特点；
(3) 综合掌握java GUI 程序设计结构；
(4) 综合掌握java多线程编程模型；
(5) 综合编程练习。
2、实验内容和步骤
任务1：填写课程课后调查问卷，网址：https://www.wjx.cn/jq/33108969.aspx。
任务2：综合编程练习
练习1：设计一个用户信息采集程序，要求如下：
（1） 用户信息输入界面如下图所示:
（1）用户点击提交按钮时，用户输入信息显示控制台界面；
（2）用户点击重置按钮后，清空用户已输入信息；
（3）点击窗口关闭，程序退出。
1 2 2 import java.awt.Dimension; 3 import java.awt.FlowLayout; 4 import java.awt.GridLayout; 5 6 import javax.swing.BorderFactory; 7 import javax.swing.ButtonGroup; 8 import javax.swing.JButton; 9 import javax.swing.JCheckBox; 10 import javax.swing.JComboBox; 11 import javax.swing.JFrame; 12 import javax.swing.JLabel; 13 import javax.swing.JPanel; 14 import javax.swing.JRadioButton; 15 import javax.swing.JTextField; 16 17 public class DemoJFrame extends JFrame { 18 private JPanel jPanel1; 19 private JPanel jPanel2; 20 private JPanel jPanel3; 21 private JPanel jPanel4; 22 private JTextField fieldname; 23 private JComboBox comboBox; 24 private JTextField fieldadress; 25 private ButtonGroup bg; 26 private JRadioButton Male; 27 private JRadioButton Female; 28 private JCheckBox read; 29 private JCheckBox sing; 30 private JCheckBox dance; 31 32 public DemoJFrame() { 33 // 设置窗口大小 34 this.setSize(800, 400); 35 // 设置可见性 36 this.setVisible(true); 37 // 设置标题 38 this.setTitle("编程练习一"); 39 // 设置关闭操作 40 this.setDefaultCloseOperation(EXIT_ON_CLOSE); 41 // 设置窗口居中 42 WinCenter.center(this); 43 // 创建四个面板对象 44 jPanel1 = new JPanel(); 45 setJPanel1(jPanel1); 46 jPanel2 = new JPanel(); 47 setJPanel2(jPanel2); 48 jPanel3 = new JPanel(); 49 setJPanel3(jPanel3); 50 jPanel4 = new JPanel(); 51 setJPanel4(jPanel4); 52 // 设置容器的为流布局 53 FlowLayout flowLayout = new FlowLayout(); 54 this.setLayout(flowLayout); 55 // 将四个面板添加到容器中 56 this.add(jPanel1); 57 this.add(jPanel2); 58 this.add(jPanel3); 59 this.add(jPanel4); 60 61 } 62 63 /* 64 * 设置面一 65 */ 66 private void setJPanel1(JPanel jPanel) { 67 // TODO 自动生成的方法存根 68 jPanel.setPreferredSize(new Dimension(700, 45)); 69 // 给面板的布局设置为网格布局 一行4列 70 jPanel.setLayout(new GridLayout(1, 4)); 71 72 JLabel name = new JLabel("name:"); 73 name.setSize(100, 50); 74 fieldname = new JTextField(""); 75 fieldname.setSize(80, 20); 76 77 JLabel study = new JLabel("qualification:"); 78 comboBox = new JComboBox(); 79 comboBox.addItem("初中"); 80 comboBox.addItem("高中"); 81 comboBox.addItem("本科"); 82 jPanel.add(name); 83 jPanel.add(fieldname); 84 jPanel.add(study); 85 jPanel.add(comboBox); 86 87 } 88 89 /* 90 * 设置面板二 91 */ 92 private void setJPanel2(JPanel jPanel) { 93 // TODO 自动生成的方法存根 94 jPanel.setPreferredSize(new Dimension(700, 50)); 95 // 给面板的布局设置为网格布局 一行4列 96 jPanel.setLayout(new GridLayout(1, 4)); 97 98 JLabel name = new JLabel("address:"); 99 fieldadress = new JTextField(); 100 fieldadress.setPreferredSize(new Dimension(150, 50)); 101 102 JLabel study = new JLabel("hobby:"); 103 JPanel selectBox = new JPanel(); 104 selectBox.setBorder(BorderFactory.createTitledBorder("")); 105 selectBox.setLayout(new GridLayout(3, 1)); 106 read = new JCheckBox("reading"); 107 sing = new JCheckBox("singing"); 108 dance = new JCheckBox("danceing"); 109 selectBox.add(read); 110 selectBox.add(sing); 111 selectBox.add(dance); 112 jPanel.add(name); 113 jPanel.add(fieldadress); 114 jPanel.add(study); 115 jPanel.add(selectBox); 116 } 117 118 /* 119 * 设置面板三 120 */ 121 private void setJPanel3(JPanel jPanel) { 122 // TODO 自动生成的方法存根 123 jPanel.setPreferredSize(new Dimension(700, 150)); 124 FlowLayout flowLayout = new FlowLayout(FlowLayout.LEFT); 125 jPanel.setLayout(flowLayout); 126 JLabel sex = new JLabel("性别:"); 127 JPanel selectBox = new JPanel(); 128 selectBox.setBorder(BorderFactory.createTitledBorder("")); 129 selectBox.setLayout(new GridLayout(2, 1)); 130 bg = new ButtonGroup(); 131 Male = new JRadioButton("male"); 132 Female = new JRadioButton("female"); 133 bg.add(Male ); 134 bg.add(Female); 135 selectBox.add(Male); 136 selectBox.add(Female); 137 jPanel.add(sex); 138 jPanel.add(selectBox); 139 140 } 141 142 /* 143 * 设置面板四 144 */ 145 private void setJPanel4(JPanel jPanel) { 146 // TODO 自动生成的方法存根 147 jPanel.setPreferredSize(new Dimension(700, 150)); 148 FlowLayout flowLayout = new FlowLayout(FlowLayout.CENTER, 50, 10); 149 jPanel.setLayout(flowLayout); 150 jPanel.setLayout(flowLayout); 151 JButton sublite = new JButton("提交"); 152 JButton reset = new JButton("重置"); 153 sublite.addActionListener((e) -> valiData()); 154 reset.addActionListener((e) -> Reset()); 155 jPanel.add(sublite); 156 jPanel.add(reset); 157 } 158 159 /* 160 * 提交数据 161 */ 162 private void valiData() { 163 // TODO 自动生成的方法存根 164 // 拿到数据 165 String name = fieldname.getText().toString().trim(); 166 String xueli = comboBox.getSelectedItem().toString().trim(); 167 String address = fieldadress.getText().toString().trim(); 168 System.out.println(name); 169 System.out.println(xueli); 170 String hobbystring=""; 171 if (read.isSelected()) { 172 hobbystring+="reading "; 173 } 174 if (sing.isSelected()) { 175 hobbystring+="singing "; 176 } 177 if (dance.isSelected()) { 178 hobbystring+="dancing "; 179 } 180 System.out.println(address); 181 if (Male.isSelected()) { 182 System.out.println("male"); 183 } 184 if (Female.isSelected()) { 185 System.out.println("female"); 186 } 187 System.out.println(hobbystring); 188 } 189 190 /* 191 * 重置 192 */ 193 private void Reset() { 194 // TODO 自动生成的方法存根 195 fieldadress.setText(null); 196 fieldname.setText(null); 197 comboBox.setSelectedIndex(0); 198 read.setSelected(false); 199 sing.setSelected(false); 200 dance.setSelected(false); 201 bg.clearSelection(); 202 } 203 } 204 205 DemoJFrame
1 2 2 3 4 import java.awt.EventQueue; 5 6 import javax.swing.JFrame; 7 8 public class Main { 9 public static void main(String[] args) { 10 EventQueue.invokeLater(() -> { 11 DemoJFrame page = new DemoJFrame(); 12 }); 13 } 14 } 15 16 Main
1 2 2 import java.awt.Dimension; 3 import java.awt.Toolkit; 4 import java.awt.Window; 5 6 public class WinCenter { 7 public static void center(Window win){ 8 Toolkit tkit = Toolkit.getDefaultToolkit(); 9 Dimension sSize = tkit.getScreenSize(); 10 Dimension wSize = win.getSize(); 11 if(wSize.height > sSize.height){ 12 wSize.height = sSize.height; 13 } 14 if(wSize.width > sSize.width){ 15 wSize.width = sSize.width; 16 } 17 win.setLocation((sSize.width - wSize.width)/ 2, (sSize.height - wSize.height)/ 2); 18 } 19 } 20 21 WinCenter
运行结果如下：
练习2：采用GUI界面设计以下程序：
l 编制一个程序，将身份证号.txt 中的信息读入到内存中；
l 按姓名字典序输出人员信息；
l 查询最大年龄的人员信息；
l 查询最小年龄人员信息；
l 输入你的年龄，查询身份证号.txt中年龄与你最近人的姓名、身份证号、年龄、性别和出生地；
l 查询人员中是否有你的同乡。
l 输入身份证信息，查询所提供身份证号的人员信息，要求输入一个身份证数字时，查询界面就显示满足查询条件的查询结果，且随着输入的数字的增多，查询匹配的范围逐渐缩小。
1 import java.io.BufferedReader; 2 import java.io.File; 3 import java.io.FileInputStream; 4 import java.io.InputStreamReader; 5 import java.io.FileNotFoundException; 6 import java.io.IOException; 7 import java.util.ArrayList; 8 import java.util.Arrays; 9 import java.util.Collections; 10 import java.util.Scanner; 11 import java.awt.*; 12 import javax.swing.*; 13 import java.awt.event.*; 14 15 public class Main extends JFrame { 16 private static ArrayList<Student> studentlist; 17 private static ArrayList<Student> list; 18 private JPanel panel; 19 private JPanel buttonPanel; 20 private static final int DEFAULT_WITH = 800; 21 private static final int DEFAULT_HEIGHT = 600; 22 23 public Main() { 24 studentlist = new ArrayList<>(); 25 Scanner scanner = new Scanner(System.in); 26 File file = new File("E:\\java\\身份证号.txt"); 27 try { 28 FileInputStream fis = new FileInputStream(file); 29 BufferedReader in = new BufferedReader(new InputStreamReader(fis)); 30 String temp = null; 31 while ((temp = in.readLine()) != null) { 32 33 Scanner linescanner = new Scanner(temp); 34 35 linescanner.useDelimiter(" "); 36 String name = linescanner.next(); 37 String number = linescanner.next(); 38 String sex = linescanner.next(); 39 String age = linescanner.next(); 40 String province = linescanner.nextLine(); 41 Student student = new Student(); 42 student.setName(name); 43 student.setnumber(number); 44 student.setsex(sex); 45 int a = Integer.parseInt(age); 46 student.setage(a); 47 student.setprovince(province); 48 studentlist.add(student); 49 50 } 51 } catch (FileNotFoundException e) { 52 System.out.println("学生信息文件找不到"); 53 e.printStackTrace(); 54 } catch (IOException e) { 55 System.out.println("学生信息文件读取错误"); 56 e.printStackTrace(); 57 } 58 panel = new JPanel(); 59 panel.setLayout(new BorderLayout()); 60 JTextArea jt = new JTextArea(); 61 panel.add(jt); 62 add(panel, BorderLayout.NORTH); 63 buttonPanel = new JPanel(); 64 buttonPanel.setLayout(new GridLayout(1, 7)); 65 JButton jButton = new JButton("字典排序"); 66 JButton jButton1 = new JButton("年龄最大和年龄最小"); 67 JLabel lab = new JLabel("猜猜你的老乡"); 68 JTextField jt1 = new JTextField(); 69 JLabel lab1 = new JLabel("找找同龄人（年龄相近）："); 70 JTextField jt2 = new JTextField(); 71 JLabel lab2 = new JLabel("输入你的身份证号码："); 72 JTextField jt3 = new JTextField(); 73 JButton jButton2 = new JButton("退出"); 74 jButton.setBounds(110, 90, 60, 30); 75 jButton1.setBounds(110, 90, 60, 30); 76 jt1.setBounds(110, 90, 60, 30); 77 jt2.setBounds(110, 90, 60, 30); 78 jt3.setBounds(110, 90, 60, 30); 79 jButton2.setBounds(110, 90, 60, 30); 80 jButton.addActionListener(new ActionListener() { 81 public void actionPerformed(ActionEvent e) { 82 Collections.sort(studentlist); 83 jt.setText(studentlist.toString()); 84 } 85 }); 86 jButton1.addActionListener(new ActionListener() { 87 public void actionPerformed(ActionEvent e) { 88 int max = 0, min = 100; 89 int j, k1 = 0, k2 = 0; 90 for (int i = 1; i < studentlist.size(); i++) { 91 j = studentlist.get(i).getage(); 92 if (j > max) { 93 max = j; 94 k1 = i; 95 } 96 if (j < min) { 97 min = j; 98 k2 = i; 99 } 100 101 } 102 jt.setText("年龄最大：" + studentlist.get(k1) + "年龄最小：" + studentlist.get(k2)); 103 } 104 }); 105 jButton2.addActionListener(new ActionListener() { 106 public void actionPerformed(ActionEvent e) { 107 dispose(); 108 System.exit(0); 109 } 110 }); 111 jt1.addActionListener(new ActionListener() { 112 public void actionPerformed(ActionEvent e) { 113 String find = jt1.getText(); 114 String text=""; 115 String place = find.substring(0, 3); 116 for (int i = 0; i < studentlist.size(); i++) { 117 if (studentlist.get(i).getprovince().substring(1, 4).equals(place)) { 118 text+="\n"+studentlist.get(i); 119 jt.setText("老乡：" + text); 120 } 121 } 122 } 123 }); 124 jt2.addActionListener(new ActionListener() { 125 public void actionPerformed(ActionEvent e) { 126 String yourage = jt2.getText(); 127 int a = Integer.parseInt(yourage); 128 int near = agenear(a); 129 int value = a - studentlist.get(near).getage(); 130 jt.setText("年龄相近：" + studentlist.get(near)); 131 } 132 }); 133 jt3.addActionListener(new ActionListener() { 134 public void actionPerformed(ActionEvent e) { 135 list = new ArrayList<>(); 136 Collections.sort(studentlist); 137 String key = jt3.getText(); 138 for (int i = 1; i < studentlist.size(); i++) { 139 if (studentlist.get(i).getnumber().contains(key)) { 140 list.add(studentlist.get(i)); 141 jt.setText("emmm！你可能是：\n" + list); 142 143 } 144 } 145 } 146 }); 147 buttonPanel.add(jButton); 148 buttonPanel.add(jButton1); 149 buttonPanel.add(lab); 150 buttonPanel.add(jt1); 151 buttonPanel.add(lab1); 152 buttonPanel.add(jt2); 153 buttonPanel.add(lab2); 154 buttonPanel.add(jt3); 155 buttonPanel.add(jButton2); 156 add(buttonPanel, BorderLayout.SOUTH); 157 setSize(DEFAULT_WITH, DEFAULT_HEIGHT); 158 } 159 160 public static int agenear(int age) { 161 int min = 53, value = 0, k = 0; 162 for (int i = 0; i < studentlist.size(); i++) { 163 value = studentlist.get(i).getage() - age; 164 if (value < 0) 165 value = -value; 166 if (value < min) { 167 min = value; 168 k = i; 169 } 170 } 171 return k; 172 } 173 174 }
1 public class Student implements Comparable<Student> { 2 3 private String name; 4 private String number ; 5 private String sex ; 6 private int age; 7 private String province; 8 9 public String getName() { 10 return name; 11 } 12 public void setName(String name) { 13 this.name = name; 14 } 15 public String getnumber() { 16 return number; 17 } 18 public void setnumber(String number) { 19 this.number = number; 20 } 21 public String getsex() { 22 return sex ; 23 } 24 public void setsex(String sex ) { 25 this.sex =sex ; 26 } 27 public int getage() { 28 29 return age; 30 } 31 public void setage(int age) { 32 // int a = Integer.parseInt(age); 33 this.age= age; 34 } 35 36 public String getprovince() { 37 return province; 38 } 39 public void setprovince(String province) { 40 this.province=province ; 41 } 42 43 public int compareTo(Student o) { 44 return this.name.compareTo(o.getName()); 45 } 46 47 public String toString() { 48 return name+"\t"+sex+"\t"+age+"\t"+number+"\t"+province+"\n"; 49 } 50 }
1 import java.awt.*; 2 import javax.swing.*; 3 4 public class ButtonTest { 5 public static void main(String[] args) { 6 EventQueue.invokeLater(() -> { 7 JFrame frame = new Main(); 8 frame.setTitle("身份证信息"); 9 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 10 frame.setVisible(true); 11 }); 12 } 13 }
运行结果如下：
练习3：采用GUI界面设计以下程序
l 编写一个计算器类，可以完成加、减、乘、除的操作
l 利用计算机类，设计一个小学生100以内数的四则运算练习程序，由计算机随机产生10道加减乘除练习题，学生输入答案，由程序检查答案是否正确，每道题正确计10分，错误不计分，10道题测试结束后给出测试总分；
l 将程序中测试练习题及学生答题结果输出到文件，文件名为test.txt。
1 import java.awt.BorderLayout; 2 import java.awt.GridLayout; 3 import java.awt.event.ActionEvent; 4 import java.awt.event.ActionListener; 5 import javax.swing.JButton; 6 import javax.swing.JFrame; 7 import javax.swing.JPanel; 8 import javax.swing.JTextField; 9 public class Calculator extends JFrame { 10 JButton b0 = new JButton("0"); 11 JButton b1 = new JButton("1"); 12 JButton b2 = new JButton("2"); 13 JButton b3 = new JButton("3"); 14 JButton b4 = new JButton("4"); 15 JButton b5 = new JButton("5"); 16 JButton b6 = new JButton("6"); 17 JButton b7 = new JButton("7"); 18 JButton b8 = new JButton("8"); 19 JButton b9 = new JButton("9"); 20 JButton jiaButton = new JButton("+"); 21 JButton jianButton = new JButton("-"); 22 JButton chengButton = new JButton("*"); 23 JButton chuButton = new JButton("/"); 24 JButton yuButton = new JButton("%"); 25 JButton jjButton = new JButton("+/-"); 26 JButton sqrtButton = new JButton("sqrt"); 27 JButton dianButton = new JButton("."); 28 JButton dengButton = new JButton("="); 29 JButton daoButton = new JButton("1/x"); 30 JButton backButton = new JButton("Backpace"); 31 JButton cButton = new JButton("C"); 32 public double op1; 33 public double op2; 34 public static final int JIA = 0; 35 public static final int JIAN = 1; 36 public static final int CHENG = 2; 37 public static final int CHU = 3; 38 public static final int JJ = 4; 39 public static final int DIAN = 5; 40 public int current0p = 0; 41 private boolean opEnd = false; 42 JPanel panel1 = new JPanel(); 43 JPanel panel2 = new JPanel(); 44 JPanel panel3 = new JPanel(); 45 JPanel panel4 = new JPanel(); 46 JTextField result = new JTextField(20); 47 public Calculator() { 48 initPanel2(); 49 initPanel3(); 50 panel2.setLayout(new GridLayout(5, 4)); 51 panel1.setLayout(new BorderLayout()); 52 panel1.add(panel3, BorderLayout.NORTH);// 设置位置 53 panel1.add(panel2, BorderLayout.CENTER);// 设置位置 54 getContentPane().add(panel1); 55 addActionListeners(); 56 setSize(260, 260); 57 setLocation(500, 300); 58 setVisible(true); 59 setDefaultCloseOperation(Calculator.EXIT_ON_CLOSE); 60 this.setResizable(false); 61 this.setTitle("计算器"); 62 } 63 private void initPanel2() { 64 // 把组件添加相应panel上 65 panel2.add(b7); 66 panel2.add(b8); 67 panel2.add(b9); 68 panel2.add(chuButton); 69 panel2.add(b4); 70 panel2.add(b5); 71 panel2.add(b6); 72 panel2.add(chengButton); 73 panel2.add(b1); 74 panel2.add(b2); 75 panel2.add(b3); 76 panel2.add(jianButton); 77 panel2.add(b0); 78 panel2.add(jjButton); 79 panel2.add(dianButton); 80 panel2.add(jiaButton); 81 panel2.add(daoButton); 82 panel2.add(yuButton); 83 panel2.add(sqrtButton); 84 panel2.add(dengButton); 85 } 86 private void addActionListeners() { 87 ActionHandler c = new ActionHandler(); 88 b0.addActionListener(c); 89 b1.addActionListener(c); 90 b2.addActionListener(c); 91 b3.addActionListener(c); 92 b4.addActionListener(c); 93 b5.addActionListener(c); 94 b6.addActionListener(c); 95 b7.addActionListener(c); 96 b8.addActionListener(c); 97 b9.addActionListener(c); 98 jiaButton.addActionListener(c); 99 dengButton.addActionListener(c); 100 chengButton.addActionListener(c); 101 chuButton.addActionListener(c); 102 jianButton.addActionListener(c); 103 jjButton.addActionListener(c); 104 dianButton.addActionListener(c); 105 sqrtButton.addActionListener(c); 106 yuButton.addActionListener(c); 107 daoButton.addActionListener(c); 108 backButton.addActionListener(c); 109 cButton.addActionListener(c); 110 } 111 class ActionHandler implements ActionListener { 112 public void actionPerformed(ActionEvent e) { 113 if (e.getSource() == b0) { 114 if (opEnd == false) { 115 result.setText(""); 116 } 117 result.setText(result.getText() + "0"); 118 } 119 if (e.getSource() == b1) { 120 if (opEnd == false) { 121 result.setText(""); 122 } 123 result.setText(result.getText() + "1"); 124 opEnd = true; 125 } 126 if (e.getSource() == b2) { 127 if (opEnd == false) { 128 result.setText(""); 129 } 130 result.setText(result.getText() + "2"); 131 opEnd = true; 132 } 133 if (e.getSource() == b3) { 134 if (opEnd == false) { 135 result.setText(""); 136 } 137 result.setText(result.getText() + "3"); 138 opEnd = true; 139 } 140 if (e.getSource() == b4) { 141 if (opEnd == false) { 142 result.setText(""); 143 } 144 result.setText(result.getText() + "4"); 145 opEnd = true; 146 } 147 if (e.getSource() == b5) { 148 if (opEnd == false) { 149 result.setText(""); 150 } 151 result.setText(result.getText() + "5"); 152 opEnd = true; 153 } 154 if (e.getSource() == b6) { 155 if (opEnd == false) { 156 result.setText(""); 157 } 158 result.setText(result.getText() + "6"); 159 opEnd = true; 160 } 161 if (e.getSource() == b7) { 162 if (opEnd == false) { 163 result.setText(""); 164 } 165 result.setText(result.getText() + "7"); 166 opEnd = true; 167 } 168 if (e.getSource() == b8) { 169 if (opEnd == false) { 170 result.setText(""); 171 } 172 result.setText(result.getText() + "8"); 173 opEnd = true; 174 } 175 if (e.getSource() == b9) { 176 if (opEnd == false) { 177 result.setText(""); 178 } 179 result.setText(result.getText() + "9"); 180 opEnd = true; 181 } 182 try { 183 if (e.getSource() == jiaButton) { 184 op1 = Double.parseDouble(result.getText()); 185 // 2、说明操作数已经输入完毕 186 opEnd = false; 187 current0p = JIA; 188 } 189 if (e.getSource() == chengButton) { 190 op1 = Double.parseDouble(result.getText()); 191 // 2、说明操作数已经输入完毕 192 opEnd = false; 193 current0p = CHENG; 194 } 195 if (e.getSource() == chuButton) { 196 op1 = Double.parseDouble(result.getText()); 197 // 2、说明操作数已经输入完毕 198 opEnd = false; 199 current0p = CHU; 200 } 201 if (e.getSource() == jianButton) { 202 op1 = Double.parseDouble(result.getText()); 203 // 2、说明操作数已经输入完毕 204 opEnd = false; 205 current0p = JIAN; 206 } 207 if (e.getSource() == jjButton) { 208 String tmp = result.getText(); 209 if (tmp.equals("") || tmp.equals("0")) { 210 return; 211 } 212 if (tmp.charAt(0) == '-') { 213 tmp = tmp.substring(1); 214 } else { 215 tmp = '-' + tmp; 216 } 217 result.setText(tmp); 218 } 219 if (e.getSource() == dianButton) { 220 String tmp = result.getText(); 221 if (tmp.equals("")) { 222 return; 223 } 224 if (tmp.indexOf(".") != -1) { 225 return; 226 } 227 tmp = tmp + "."; 228 result.setText(tmp); 229 } 230 if (e.getSource() == sqrtButton) { 231 String tmp = result.getText(); 232 if (tmp.equals(" ")) { 233 return; 234 } 235 double d; 236 d = Double.parseDouble(tmp);// 先定义double类型d 237 if (d < 0) { 238 result.setText("不能对负数求平方根"); 239 return; 240 } 241 op2 = Math.sqrt(d); 242 result.setText(op2 + ""); 243 } 244 if (e.getSource() == backButton) { 245 String s = result.getText(); 246 result.setText(""); 247 for (int i = 0; i < s.length() - 1; i++) { 248 char a = s.charAt(i); 249 result.setText(result.getText() + a); 250 } 251 } 252 if (e.getSource() == cButton) { 253 result.setText("0"); 254 opEnd = false; 255 } 256 if (e.getSource() == dengButton) { 257 op2 = Double.parseDouble(result.getText()); 258 switch (current0p) { 259 case JIA: 260 result.setText(op1 + op2 + ""); 261 break; 262 case JIAN: 263 result.setText(op1 - op2 + ""); 264 break; 265 case CHENG: 266 result.setText(op1 * op2 + ""); 267 break; 268 case CHU: 269 if (op2 == 0) { 270 result.setText("被除数不能为零"); 271 break; 272 } 273 result.setText(op1 / op2 + ""); 274 break; 275 } 276 opEnd = false; 277 } 278 } catch (Exception e1) { 279 result.setText("Wrong"); 280 opEnd = false; 281 } 282 } 283 } 284 private void initPanel3() { 285 panel3.setLayout(new GridLayout(2, 1)); 286 panel3.add(result); 287 panel3.add(panel4); 288 panel4.setLayout(new GridLayout(1, 2)); 289 panel4.add(backButton); 290 panel4.add(cButton); 291 } 292 public static void main(String[] args) { 293 Calculator c = new Calculator();// 生成类实例 294 } 295 }
1 import java.io.FileNotFoundException; 2 import java.io.PrintWriter; 3 import java.util.Scanner; 4 5 /* 6 * 该程序用来随机生成0到100以内的加减乘除题 7 */ 8 public class Demo { 9 public static void main(String[] args) { 10 // 用户的答案要从键盘输入，因此需要一个键盘输入流 11 Scanner in = new Scanner(System.in); 12 Counter counter=new Counter(); 13 PrintWriter out = null; 14 try { 15 out = new PrintWriter("text.txt"); 16 } catch (FileNotFoundException e) { 17 // TODO Auto-generated catch block 18 e.printStackTrace(); 19 } 20 // 定义一个变量用来统计得分 21 int sum = 0; 22 int k=0; 23 // 通过循环生成10道题 24 for (int i = 0; i < 10; i++) { 25 26 // 随机生成两个100以内的随机数作加减乘除 27 int a = (int) Math.round(Math.random() * 100); 28 int b = (int) Math.round(Math.random() * 100); 29 int d = (int) Math.round(Math.random() * 3); 30 31 switch (d){ 32 33 case 0: 34 if(a%b == 0) { 35 System.out.println(a + "/" + b + "="); 36 break; 37 } 38 //int c = in.nextInt(); 39 //out.println(a + "/" + b + "="+c); 40 case 1: 41 System.out.println(a + "*" + b + "="); 42 //int c1 = in.nextInt(); 43 //out.println(a + "*" + b + "="+c1); 44 break; 45 case 2: 46 System.out.println(a + "+" + b + "="); 47 //int c2 = in.nextInt(); 48 //out.println(a + "+" + b + "="+c2); 49 break; 50 case 3: 51 if(a>b) { 52 System.out.println(a + "-" + b + "="); 53 break; 54 } 55 //int c3 = in.nextInt(); 56 //out.println(a + "-" + b + "="+c3); 57 58 } 59 60 // 定义一个整数用来接收用户输入的答案 61 double c = in.nextDouble(); 62 63 // 判断用户输入的答案是否正确，正确给10分，错误不给分 64 if (c == a / b | c == a * b | c == a + b | c == a - b) { 65 sum += 10; 66 System.out.println("恭喜答案正确"); 67 } 68 else { 69 System.out.println("抱歉，答案错误"); 70 71 } 72 out.println(a + "/" + b + "="+c ); 73 out.println(a + "*" + b + "="+c); 74 out.println(a + "+" + b + "="+c); 75 out.println(a + "-" + b + "="+c); 76 77 } 78 //输出用户的成绩 79 System.out.println("你的得分为"+sum); 80 81 out.println("成绩:"+sum); 82 out.close(); 83 } 84 }
运行结果如下：
任务3：本学期课程已结束，请汇总《面向对象程序设计课程学习进度条》的数据，统计个人专业能力提升的数据。并从学习内容、学习方法、学习心得几个方面进行课程学习总结，也希望你对课程的不足提出建议和意见。
4. 实验总结：
通过本学期的实验课程学习，真的学到了很多，尤其是在老师和助教学长的耐心指导下，从最开始JDK的安装到后来自己能写出可以运行的程序，很开心。这并不是结束，而是另一个新的开始，我会继续努力，学习更多。