自考JAVA语言程序设计一课后习题答案与源代码实验大纲.docx

1、自考JAVA语言程序设计一课后习题答案与源代码实验大纲实验大纲1 字符统计程序程序运行结果：统计字符源文件：StaChar.javaimport javax.swing.*;/* * 1 字符统计程序 * 利用对话框读入字符串 统计输入字符行中数字字符、英文字母个数. * author 黎明你好 */public class StaChar public static void main(String args) String str = JOptionPane.showInputDialog(请输入字符串：); char c = str.toCharArray(); int numberCo

2、unt = 0; int letterCount = 0; for (int i = 0; i c.length; i+) if (ci 0) numberCount+; else if (ci A & ci a & ci z) letterCount+; String result = 输入内容：n + str + n数字字符： + numberCount + 个； + n字母： + letterCount + 个; JOptionPane.showMessageDialog(null, result, 结果：, JOptionPane.INFORMATION_MESSAGE); 2 找质数

3、程序程序运行结果：输出质数原文件：PrintPrime.javaimport javax.swing.JOptionPane;/* * 2 找质数程序,利用对话框读入整数,输出2至这个整数之间的质数. * author 黎明你好 */public class PrintPrime private int number;/ 正整数 private String result = ; public PrintPrime()/ 构造方法 number = getIntegerNumber(输入整数n, 0);/ 要求是=0的整数 if (number 0) return;/ 出现错误，程序结束 el

4、se / 如果大于等于2，开始用循环计算结果 for (int i = 2; i = number; i+) / 计算素数和 if (isPrimeNumber(i) result += i + ; / 显示最后的和 JOptionPane.showMessageDialog(null, number + 之前所有素数为：n “ + result + ”, 显示结果, JOptionPane.INFORMATION_MESSAGE); /* * 通过图形界面，得到符合规则的正整数的方法 * param message - 在弹出的对话框中，显示提示信息 * param min - 要求此数必须

5、大于等于min * return - 返回符合规则的整数 */ public int getIntegerNumber(String message, int min) String str = JOptionPane.showInputDialog(null, message, 提示信息, JOptionPane.INFORMATION_MESSAGE); int number = -1; try number = Integer.parseInt(str); / 得到输入的正整数 catch( Exception e ) JOptionPane.showMessageDialog(null

6、, 输入非数字字符n程序结束, 错误警告, JOptionPane.ERROR_MESSAGE); return -1; / 输入的不是数字字符，程序结束 if (number min) JOptionPane.showMessageDialog(null, 输入的数不符合规则，不是正整数n程序结束, 错误警告, JOptionPane.ERROR_MESSAGE); return -1; / 输入的数不是大于2的正整数时候，程序结束 else return number; /* * 判断是否是素数的方法 * param n - 需要判断的数 * return - 是素数返回true，否则返回

7、false */ public boolean isPrimeNumber(int n) for (int i = 2; i n; i+) if (n % i = 0) return false; return true; /* main方法 */ public static void main(String args) new PrintPrime(); 3 类的继承定义，包括几何形状类Shape、圆形类Circle.、矩形类Rectangle/* * 几何图形类，抽象类 */abstract class Shape public float area() return 0.0f; /* *

8、 圆形类 */class Circle extends Shape private float R; public Circle(float r) R = r; public float area() return (float) (Math.PI * R * R); /* * 矩形类 */class Rectangle extends Shape private float w, h; public Rectangle(float w, float h) this.w = w; this.h = h; public float area() return w * h; public clas

9、s Work11_3 public static void main(String args) Circle c; Rectangle r; c = new Circle(2.0f); r = new Rectangle(3.0f, 5.0f); System.out.println(圆面积 + returnArea(c); System.out.println(长方形面积 + returnArea(r); static float returnArea(Shape s) return s.area(); 4 数组排序程序源文件：Work11_4.javaimport javax.swing.

10、*;import java.util.*;/* * 4 数组排序程序. * 输入整数序列,对输入的整数进行排序,输出结果. * author 黎明你好 */public class Work11_4 public static final int RISE = 0; public static final int LOWER = 1; public static void main(String args) String str = JOptionPane.showInputDialog(请输入字符串：); StringTokenizer token = new StringTokenizer

11、(str, ,.;: ); int mode = Work11_4.RISE;/ 排列模式，默认为升序排列 int count = token.countTokens();/ 输入的整数的个数 int array = new intcount; int index = 0; while (token.hasMoreTokens() try arrayindex = Integer.parseInt(token.nextToken(); index+; catch( Exception e ) JOptionPane.showMessageDialog(null, 输入非法字符, 错误警告, J

12、OptionPane.ERROR_MESSAGE); return;/ 输入非法字符时候，直接结束程序 sort(array, mode);/ 按mode模式，进行排序 String result = new String(); String modeString = new String(); if (mode = Work11_4.RISE) modeString = 升序排列结果为：; if (mode = Work11_4.LOWER) modeString = 降序排列结果为：; for (int i = 0; i array.length; i+) result = result

13、+ arrayi + ，; if (result != null) JOptionPane .showMessageDialog(null, result, modeString, JOptionPane.INFORMATION_MESSAGE); /* * 给数组排序的方法 * param array - 需要排序的数组 * param mode - 排序的模式，可以为RISE，LOWER */ public static void sort(int array, int mode) for (int i = 0; i array.length; i+) for (int j = 0; j

14、arrayj + 1) int temp = arrayj; arrayj = arrayj + 1; arrayj + 1 = temp; if (mode = Work11_4.LOWER & arrayj arrayj + 1) int temp = arrayj; arrayj = arrayj + 1; arrayj + 1 = temp; 5 字符串处理程序，括号匹配程序运行结果：括号匹配检测源文件：CheckBrackets.javaimport java.awt.*;import java.awt.event.*;import javax.swing.*;import unit

15、9.MyFileFilter;import java.io.*;/* * 5 字符串处理程序. * 输入程序的源程序代码行,找出可能存在圆括号，花括号不匹配的错误. * author 黎明你好 */public class CheckBrackets extends JFrame implements ActionListener, ItemListener private static final long serialVersionUID = 1L; private JFileChooser fileChooser; private JButton openFileButton; priv

16、ate JComboBox comboBox; private JTextField showRowStringField; private JTextField showMessageField; private JTextArea textArea; private JPanel northPanel, control_panel; private String rowString; private File file = null; public CheckBrackets() super(检测圆、花括号匹配程序); fileChooser = new JFileChooser(Syst

17、em.getProperty(user.dir); openFileButton = new JButton(打开文件); showRowStringField = new JTextField(); showMessageField = new JTextField(20); textArea = new JTextArea(); comboBox = new JComboBox(); northPanel = new JPanel(); control_panel = new JPanel(); rowString = new String1000; fileChooser.addChoo

18、sableFileFilter(new MyFileFilter(txt);/文件筛选 textArea.setLineWrap(true); showRowStringField.setEditable(false); showRowStringField.setBackground(Color.WHITE); showMessageField.setEditable(false); showMessageField.setBackground(Color.WHITE); openFileButton.addActionListener(this); comboBox.addItemList

19、ener(this); comboBox.addItem(请选择); control_panel.add(openFileButton); control_panel.add(new JLabel( 选择代码行:); control_panel.add(comboBox); control_panel.add(new JLabel(检测结果:); control_panel.add(showMessageField); northPanel.setLayout(new GridLayout(2, 1, 10, 10); northPanel.add(control_panel); northP

20、anel.add(showRowStringField); this.add(northPanel, BorderLayout.NORTH); this.add(new JScrollPane(textArea), BorderLayout.CENTER); this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); this.setBounds(50, 50, 550, 500); this.setVisible(true); this.validate(); public void actionPerformed(ActionEvent e)

21、showMessageField.setText(); int message = fileChooser.showOpenDialog(this); if (message = JFileChooser.APPROVE_OPTION) file = fileChooser.getSelectedFile(); comboBox.removeAllItems(); comboBox.addItem(请选择); readFile(file); public void itemStateChanged(ItemEvent e) int index = comboBox.getSelectedInd

22、ex(); if (index = 1) showRowStringField.setText(rowStringindex - 1); char c = rowStringindex - 1.toCharArray(); int count1 = 0; int count2 = 0; for (int i = 0; i c.length; i+) if (ci = ) count1+; if (ci = ) count1-; if (ci = () count2+; if (ci = ) count2-; System.out.println(大括号 + count1 + ,小括号： + c

23、ount2); if (count1 != 0) showMessageField.setText(第 + index + 行，大括号匹配错误); else if (count2 != 0) showMessageField.setText(第 + index + 行，小括号()匹配错误); else if (count1 != 0 & count2 != 0) showMessageField.setText(第 + index + 行，大、小括号都匹配错误); else if (count1 = 0 & count2 = 0) showMessageField.setText(括号匹配正确

24、); public void readFile(File f) if (f != null) try FileReader file = new FileReader(f); BufferedReader in = new BufferedReader(file); String s = new String(); int i = 0; textArea.setText(); while (s = in.readLine() != null) textArea.append(i + 1) + ： + s + n); rowStringi = s; comboBox.addItem(i + 1)

25、; i+; catch( Exception e ) System.out.println( + e.toString(); public static void main(String args) new CheckBrackets(); 6 计算器程序。程序运行结果：简易计算器程序原文件: Calculator.javaimport java.awt.*;import java.awt.event.*;import javax.swing.*;/* * 计算器程序. * 三个文本框，加、减、乘、除按钮 在前两个文本框分别输入两个运算数 点击按钮后，在第三个文本框中显示计算结果. * aut

26、hor 黎明你好 */public class Calculator extends JFrame implements ActionListener private static final long serialVersionUID = 1L; private JTextField oneField, twoField, resultField; private JButton addButton, subtractButton, multiplyButton, divideButton, cleanButton; private JPanel panel1, panel2, panel3; public Calculator() super(简易计算器); oneField = new JTextField(10); twoField = new JTextField(10); resultField = new JTextField(20); addButton = new JButton(+); subtractButton = new JButton(); multiplyButton = new JButton(*); divideButton = new JButton(/); cleanButton = new JButton