JAVA编程题系列——涵盖几乎所有java内容

自己定义一个类，有static属性和构造方法，有构造方法重载，有其他方法（方法有对String类型操作）

public class MyClass {// 静态属性public static String staticProperty = "Static Property";// 成员变量private String value;// 构造方法public MyClass(String value) {this.value = value;}// 构造方法重载public MyClass(int value) {this.value = String.valueOf(value);}// 其他方法，对字符串类型进行操作public void manipulateString(String newValue) {this.value += newValue;}// Getter方法public String getValue() {return value;}
}public class Main {public static void main(String[] args) {// 调用不同的构造方法生成两个对象MyClass obj1 = new MyClass("Hello");MyClass obj2 = new MyClass(123);// 调用其他方法obj1.manipulateString(" World");obj2.manipulateString("456");// 输出结果System.out.println("Value of obj1: " + obj1.getValue());  // 输出：Hello WorldSystem.out.println("Value of obj2: " + obj2.getValue());  // 输出：123456// 访问静态属性System.out.println("Static property: " + MyClass.staticProperty);  // 输出：Static Property}
}

定义一个Person类，有各种属性和行为，对属性建立setter和getter方法。对其中一个行为进行重载，建立一个TestPerson类，在main函数中建立Person对象，并调用对象的行为

// Person 类
public class Person {// 属性private String name;private int age;private String gender;// 构造函数public Person(String name, int age, String gender) {this.name = name;this.age = age;this.gender = gender;}// Getter 和 Setter 方法public String getName() {return name;}public void setName(String name) {this.name = name;}public int getAge() {return age;}public void setAge(int age) {this.age = age;}public String getGender() {return gender;}public void setGender(String gender) {this.gender = gender;}// 行为方法（重载）public void introduce() {System.out.println("Hello, I am " + name + ", " + age + " years old, " + gender + ".");}// 重载 introduce 方法public void introduce(String occupation) {System.out.println("Hello, I am " + name + ", " + age + " years old, " + gender + ".");System.out.println("I am a " + occupation + ".");}
}// TestPerson 类
public class TestPerson {public static void main(String[] args) {// 创建 Person 对象Person person1 = new Person("Alice", 30, "Female");// 调用对象的行为person1.introduce();// 使用重载方法person1.introduce("software engineer");// 测试 Getter 和 Setter 方法System.out.println("Before setting age: " + person1.getAge());person1.setAge(35);System.out.println("After setting age: " + person1.getAge());}
}

 

自行定义任意一个抽象的父类，有属性和方法，再自行定义两个子类，子类有不同于父类的属性和方法。同时重写父类的一个方法。用多态的形式调用子类方法，方法中涉及基本类型的包装类。写出Java程序

abstract class Shape {// 属性protected double area;// 抽象方法public abstract void calculateArea();// 方法public void displayArea() {System.out.println("Area: " + area);}
}class Circle extends Shape {// 子类属性private double radius;// 构造方法public Circle(double radius) {this.radius = radius;}// 重写父类方法@Overridepublic void calculateArea() {area = Math.PI * radius * radius;}// 子类方法public void displayRadius() {System.out.println("Radius: " + radius);}
}class Rectangle extends Shape {// 子类属性private double length;private double width;// 构造方法public Rectangle(double length, double width) {this.length = length;this.width = width;}// 重写父类方法@Overridepublic void calculateArea() {area = length * width;}// 子类方法public void displayDimensions() {System.out.println("Length: " + length + ", Width: " + width);}
}public class Main {public static void main(String[] args) {// 使用多态性调用子类方法Shape circle = new Circle(5.0);circle.calculateArea();circle.displayArea();  // 输出：Area: 78.53981633974483// 使用多态性调用子类方法Shape rectangle = new Rectangle(4.0, 6.0);rectangle.calculateArea();rectangle.displayArea();  // 输出：Area: 24.0}
}

 

输入一个日期格式为xxxx-xx-xx，如果格式不正确，抛出一个自定义日期格式异常，如果格式正确，请输出：你输入的2023-01-01是兔年，星期日，然后每隔一秒钟，输出现在是2024年2月26日，**时**分**秒

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;class InvalidDateFormatException extends Exception {public InvalidDateFormatException(String message) {super(message);}
}public class Main {public static void main(String[] args) {try {String inputDate = "2023-01-01";validateDateFormat(inputDate);// 输出输入日期信息SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");Date date = dateFormat.parse(inputDate);Calendar calendar = Calendar.getInstance();calendar.setTime(date);int year = calendar.get(Calendar.YEAR);int month = calendar.get(Calendar.MONTH) + 1;int dayOfMonth = calendar.get(Calendar.DAY_OF_MONTH);int dayOfWeek = calendar.get(Calendar.DAY_OF_WEEK);String animal = getChineseZodiac(year);String dayOfWeekString = getDayOfWeekString(dayOfWeek);System.out.println("你输入的" + inputDate + "是" + animal + "年，" + dayOfWeekString);// 模拟每隔一秒钟输出当前日期时间while (true) {Thread.sleep(1000); // 等待1秒calendar.add(Calendar.SECOND, 1); // 增加1秒year = calendar.get(Calendar.YEAR);month = calendar.get(Calendar.MONTH) + 1;int day = calendar.get(Calendar.DAY_OF_MONTH);int hour = calendar.get(Calendar.HOUR_OF_DAY);int minute = calendar.get(Calendar.MINUTE);int second = calendar.get(Calendar.SECOND);System.out.printf("现在是%d年%d月%d日，%02d时%02d分%02d秒%n", year, month, day, hour, minute, second);}} catch (InvalidDateFormatException e) {System.out.println(e.getMessage());} catch (ParseException | InterruptedException e) {e.printStackTrace();}}private static void validateDateFormat(String inputDate) throws InvalidDateFormatException {if (!inputDate.matches("\\d{4}-\\d{2}-\\d{2}")) {throw new InvalidDateFormatException("日期格式错误，请输入格式为xxxx-xx-xx的日期。");}}private static String getChineseZodiac(int year) {String[] zodiacs = {"鼠", "牛", "虎", "兔", "龙", "蛇", "马", "羊", "猴", "鸡", "狗", "猪"};return zodiacs[(year - 1900) % 12];}private static String getDayOfWeekString(int dayOfWeek) {String[] daysOfWeek = {"星期日", "星期一", "星期二", "星期三", "星期四", "星期五", "星期六"};return daysOfWeek[dayOfWeek - 1];}
}

 

自定义一个类，类中引用了泛型技术。生成几个自定义类的对象，将对象加入到集合的ArrayList或LinkList，并在集合中删除部分对象，最后在集合中删除对象的全部输出，Java程序 

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;class CustomClass<T> {private T data;public CustomClass(T data) {this.data = data;}public T getData() {return data;}public void setData(T data) {this.data = data;}
}public class Main {public static void main(String[] args) {// 创建自定义类的对象CustomClass<Integer> obj1 = new CustomClass<>(1);CustomClass<String> obj2 = new CustomClass<>("Hello");CustomClass<Double> obj3 = new CustomClass<>(3.14);// 创建ArrayList集合List<CustomClass<?>> list = new ArrayList<>();// 将对象添加到集合中list.add(obj1);list.add(obj2);list.add(obj3);// 输出集合中的对象System.out.println("初始集合中的对象：");for (CustomClass<?> obj : list) {System.out.println(obj.getData());}// 删除部分对象list.remove(obj2);// 输出删除部分对象后的集合System.out.println("删除部分对象后的集合：");for (CustomClass<?> obj : list) {System.out.println(obj.getData());}// 删除集合中的全部对象list.clear();// 输出删除全部对象后的集合System.out.println("删除全部对象后的集合：");for (CustomClass<?> obj : list) {System.out.println(obj.getData());}}
}

向一个文件输入自己的信息，然后把信息打印出来，打印在终端Java程序 

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;public class FileIOExample {public static void main(String[] args) {// 文件路径String filePath = "myInfo.txt";// 向文件输入信息writeToFile(filePath, "Name: John Doe\nAge: 25\nOccupation: Developer");// 从文件读取信息并打印在终端String fileContent = readFromFile(filePath);System.out.println("File Content:\n" + fileContent);}// 向文件写入信息private static void writeToFile(String filePath, String content) {try (BufferedWriter writer = new BufferedWriter(new FileWriter(filePath))) {writer.write(content);} catch (IOException e) {e.printStackTrace();}}// 从文件读取信息private static String readFromFile(String filePath) {StringBuilder content = new StringBuilder();try (BufferedReader reader = new BufferedReader(new FileReader(filePath))) {String line;while ((line = reader.readLine()) != null) {content.append(line).append("\n");}} catch (IOException e) {e.printStackTrace();}return content.toString();}
}

自行设计一个界面，至少包含3个基本的组件，程序包含监听事件，Java程序

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;public class SimpleGUIExample {public static void main(String[] args) {// 创建 JFrame 实例JFrame frame = new JFrame("Simple GUI Example");// 设置关闭操作frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);// 创建组件JButton button = new JButton("点击我");JTextField textField = new JTextField(20);JLabel label = new JLabel("显示区域:");// 创建面板JPanel panel = new JPanel();panel.setLayout(new FlowLayout());// 添加组件到面板panel.add(textField);panel.add(button);panel.add(label);// 添加面板到框架frame.getContentPane().add(BorderLayout.CENTER, panel);// 添加按钮点击事件监听器button.addActionListener(new ActionListener() {@Overridepublic void actionPerformed(ActionEvent e) {// 按钮点击时更新标签内容label.setText("显示区域: " + textField.getText());}});// 设置框架大小frame.setSize(300, 150);// 设置框架可见frame.setVisible(true);}
}

 

编写多线程程序，用两种方法（继承Thread，实现Runnable，卡里的前，每增加一元，自己的java技能，每秒钟增加一点

class CardThread extends Thread {private int balance = 0; // 初始卡里的金额private int javaSkill = 0; // 初始Java技能点数public void run() {while (true) {try {Thread.sleep(1000); // 线程休眠一秒钟balance++; // 每秒钟卡里的金额增加一元javaSkill++; // 每秒钟Java技能增加一点System.out.println("卡里的金额：" + balance + " 元，Java技能：" + javaSkill + " 点");} catch (InterruptedException e) {e.printStackTrace();}}}
}public class ThreadExample {public static void main(String[] args) {CardThread thread = new CardThread();thread.start(); // 启动线程}
}

 

class CardRunnable implements Runnable {private int balance = 0; // 初始卡里的金额private int javaSkill = 0; // 初始Java技能点数public void run() {while (true) {try {Thread.sleep(1000); // 线程休眠一秒钟balance++; // 每秒钟卡里的金额增加一元javaSkill++; // 每秒钟Java技能增加一点System.out.println("卡里的金额：" + balance + " 元，Java技能：" + javaSkill + " 点");} catch (InterruptedException e) {e.printStackTrace();}}}
}public class RunnableExample {public static void main(String[] args) {CardRunnable cardRunnable = new CardRunnable();Thread thread = new Thread(cardRunnable);thread.start(); // 启动线程}
}

用循环语句打印A-Z共26个字母

 

public class PrintAlphabets {public static void main(String[] args) {// Using a for loop to print A-Zfor (char ch = 'A'; ch <= 'Z'; ch++) {System.out.print(ch + " ");}// If you want to print on new lines:/*for (char ch = 'A'; ch <= 'Z'; ch++) {System.out.println(ch);}*/}
}

从键盘输入一个整数到变量a，b，c中，然后由小到大的顺序输出 

import java.util.Scanner;public class SortNumbers {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);// 输入三个整数System.out.print("请输入第一个整数 (a): ");int a = scanner.nextInt();System.out.print("请输入第二个整数 (b): ");int b = scanner.nextInt();System.out.print("请输入第三个整数 (c): ");int c = scanner.nextInt();// 关闭输入流scanner.close();// 排序并输出System.out.println("由小到大的顺序输出:");displaySortedNumbers(a, b, c);}private static void displaySortedNumbers(int a, int b, int c) {int temp;// 使用冒泡排序进行排序for (int i = 0; i < 2; i++) {for (int j = 0; j < 2 - i; j++) {if (a > b) {temp = a;a = b;b = temp;}if (b > c) {temp = b;b = c;c = temp;}}}// 输出排序后的结果System.out.println(a + " " + b + " " + c);}
}