java，实现类的定义和使用

要求：（1）创建一个student的类：属性：姓名、性别、学号；行为：说话、计算加法。编写能为所有属性赋值的构造方法。
（2）创建主类：创建一个对象：名叫“王明”，年龄19岁，性别“男”，学号00001；让该对象调用成员方法：说出“你好！”，计算19+20的值

class Student {
  // 属性：姓名、性别、学号
  private String name;
  private String gender;
  private String studentNumber;
  private int age;

  // 行为：说话、计算加法
  public void speak() {
    System.out.println("你好！");
  }

  public int add(int a, int b) {
    return a + b;
  }

  // 编写能为所有属性赋值的构造方法
  public Student(String name, int age, String gender, String studentNumber) {
    this.name = name;
    this.age = age;
    this.gender = gender;
    this.studentNumber = studentNumber;
  }
}
public class Main {
  public static void main(String[] args) {
    // 创建一个对象：名叫“王明”，年龄19岁，性别“男”，学号00001
    Student student = new Student("王明", 19, "男", "00001");

    // 让该对象调用成员方法：说出“你好！”，计算19 20的值
    student.speak();
    int result = student.add(19, 20);
    System.out.println(result);
  }
}

public class student{
private String xxxx；

xxxx
}

以下是我写的一个参考程序:

// Student类
class Student {
    // 属性：姓名、性别、学号
    private String name;
    private String gender;
    private String studentNumber;

    // 构造方法，用于为属性赋值
    public Student(String name, String gender, String studentNumber) {
        this.name = name;
        this.gender = gender;
        this.studentNumber = studentNumber;
    }

    // 行为：说话
    public void speak(String content) {
        System.out.println(name + "说：" + content);
    }

    // 行为：计算加法
    public int add(int a, int b) {
        return a + b;
    }
}

// 主类
public class Main {
    public static void main(String[] args) {
        // 创建Student对象
        Student student = new Student("王明", "男", "00001");
        // 调用对象的说话方法
        student.speak("你好！");
        // 调用对象的计算加法方法
        int result = student.add(19, 20);
        System.out.println("计算结果：" + result);
    }
}

class Student {
    // 属性
    private String name;
    private String gender;
    private String studentId;

    // 行为
    public void speak() {
        System.out.println("你好！");
    }

    public int add(int x, int y) {
        return x + y;
    }

    // 构造方法
    public Student(String name, String gender, String studentId) {
        this.name = name;
        this.gender = gender;
        this.studentId = studentId;
    }
}

public class Main {
    public static void main(String[] args) {
        // 创建对象
        Student student = new Student("王明", "男", "00001");
        // 调用成员方法
        student.speak();
        System.out.println(student.add(19, 20));
    }
}

仅供参考，望采纳，谢谢。

@Data
@AllArgsConstructor
@NoArgsConstructor
class StudentBean {
    private long id;

    private int del;

    private Timestamp createTime;

    private String name;

    private String gender;

    private String studentNumber;

    public void speak(){
        System.out.println("你好!!!");
    }

    public int calculate(int a,int b){
        return a+b;
    }
}

class StudentController {
    public static void main(String[] args) {
        StudentBean studentBean = new StudentBean(1, 0, Timestamp.valueOf(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date())), "王明", "男", "00001");

        System.out.println(studentBean);
        studentBean.speak();
        System.out.println("19 + 20 = " + studentBean.calculate(19, 20));
    }
}

class Student {
    private String name;
    private String gender;
    private String studentNumber;
    private int age;

    public Student(String name, String gender, String studentNumber, int age) {
        this.name = name;
        this.gender = gender;
        this.studentNumber = studentNumber;
        this.age = age;
    }

    public void speak(String content) {
        System.out.println(content);
    }

    public int add(int a, int b) {
        return a + b;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getGender() {
        return gender;
    }

    public void setGender(String gender) {
        this.gender = gender;
    }

    public String getStudentNumber() {
        return studentNumber;
    }

    public void setStudentNumber(String studentNumber) {
        this.studentNumber = studentNumber;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
}

public class Test {
    public static void main(String[] args) {
        Student student = new Student("王明", "男", "00001", 19);
        student.speak("你好！");
        int result = student.add(19, 20);
        System.out.println(result);
    }
}

Student.java

class Student {
    private String name;
    private String gender;
    private String no;
    private int age;

    public Student(String name, int age, String gender, String no) {
        this.name = name;
        this.gender = gender;
        this.no = no;
        this.age = age;
    }

    public void speak(String content) {
        System.out.println(content);
    }

    public int add(int a, int b) {
        return a + b;
    }


}

Main.java

public class Main {
    public static void main(String[] args) {
        Student student = new Student("王明", 19, "男", "00001");

        student.speak("你好!");
        int sum = student.add(19, 20);
        System.out.println(sum);
    }
}

输出结果:

你好!
39

Process finished with exit code 0

在 Java 中，可以使用以下代码来定义一个 Student 类：

public class Student {
    // 属性
    private String name;
    private String gender;
    private int id;

    // 行为：说话、计算加法
    public void speak() {
        System.out.println("你好！");
    }

    public int add(int a, int b) {
        return a + b;
    }

    // 构造方法：能为所有属性赋值
    public Student(String name, String gender, int id) {
        this.name = name;
        this.gender = gender;
        this.id = id;
    }
}

然后，在主类中，可以使用以下代码来创建 Student 对象并调用它的方法：

public class Main {
    public static void main(String[] args) {
        // 创建对象
        Student student = new Student("王明", "男", 00001);

        // 调用方法
        student.speak();
        int result = student.add(19, 20);
        System.out.println(result);
    }
}

代码参考

// Student 类的定义
class Student {
  // 属性
  String name;
  String gender;
  int studentId;

  // 构造方法
  public Student(String name, String gender, int studentId) {
    this.name = name;
    this.gender = gender;
    this.studentId = studentId;
  }

  // 行为：说话
  public void speak() {
    System.out.println("你好！");
  }

  // 行为：计算加法
  public int add(int a, int b) {
    return a + b;
  }
}

// 主类
class Main {
  public static void main(String[] args) {
    // 创建一个对象：名叫“王明”，性别“男”，学号00001
    Student student = new Student("王明", "男", 00001);
    // 让该对象调用成员方法：说出“你好！”
    student.speak();
    // 让该对象调用成员方法：计算19+20的值
    System.out.println(student.add(19, 20));
  }
}

望采纳

package com.itbird.test;

/**
 * Created by itbird on 2023/1/4
 */
class Student {
    /**
     * 属性：姓名、性别、学号
     */
    private String name;
    private String gender;
    private String studentNumber;
    private int age;

    // 行为：说话、计算加法
    public void speak() {
        System.out.println("你好！");
    }

    public int add(int a, int b) {
        return a + b;
    }

    // 编写能为所有属性赋值的构造方法
    public Student(String name, int age, String gender, String studentNumber) {
        this.name = name;
        this.age = age;
        this.gender = gender;
        this.studentNumber = studentNumber;
    }
}

public class Main {
    public static void main(String[] args) {
        // 创建一个对象：名叫“王明”，年龄19岁，性别“男”，学号00001
        Student student = new Student("王明", 19, "男", "00001");

        // 让该对象调用成员方法：说出“你好！”，计算19 20的值
        student.speak();
        int result = student.add(19, 20);
        System.out.println(result);
    }
}

面向对象的编程思想，首先创建对象，再次创建方法，新建main方法，直接初始化值，再次调用即可

以下是我写的一个参考程序，望采纳

class Student {
    
    /**
     * 属性：姓名、年龄、性别、学号
     */
    private String name;
    private int age;
    private String sex;
    private String stuNum;

    // 行为:说话【你好！】
    public void speak() {
        System.out.println("你好！");
    }
    //行为:计算
    public int add(int num1, int num2) {
        return num1 + num2;
    }

    //无参构造
    public Student() {
    }

    //有参构造
    public Student(String name, int age, String sex, String stuNum) {
        this.name = name;
        this.age = age;
        this.sex = sex;
        this.stuNum = stuNum;
    }
}

public class Main {
    public static void main(String[] args) {
        
        // 创建一个对象：名叫“王明”，年龄19岁，性别“男”，学号00001
        Student student = new Student("王明", 19, "男", "00001");
        // 让该对象调用成员方法：打印“你好！”
        student.speak();
        //计算19+20的值
        int result = student.add(19, 20);
        //打印计算结果
        System.out.println("计算结果：" +result);
    }
}

可以这样定义student类：

public class Student {
    // 属性
    private String name;
    private String gender;
    private String id;
    // 构造方法
    public Student(String name, String gender, String id) {
        this.name = name;
        this.gender = gender;
        this.id = id;
    }
    // 行为
    public void speak() {
        System.out.println("你好！");
    }
    public int add(int a, int b) {
        return a + b;
    }
}

然后在主类中创建对象并调用方法：

public class Main {
    public static void main(String[] args) {
        // 创建对象
        Student student = new Student("王明", "男", "00001");
        // 调用方法
        student.speak();
        int result = student.add(19, 20);
        System.out.println(result);
    }
}

这样就可以实现创建student类并使用了。

import java.util.Scanner;

class Student {
    String name;
    String gender;
    int studentId;

    public Student(String name, String gender, int studentId) {
        this.name = name;
        this.gender = gender;
        this.studentId = studentId;
    }

    public void speak() {
        System.out.println("你好！");
    }

    public int add(int a, int b) {
        return a + b;
    }
}

public class Main {
    public static void main(String[] args) {
        Student student = new Student("王明", "男", 00001);
        student.speak();
        System.out.println(student.add(19, 20));
    }
}

public class Student {
    // (1）创建一个student的类：属性：姓名、性别、学号；行为：说话、计算加法。编写能为所有属性赋值的构造方法。
    private String name;
    private String sex;
    private String stuNo;

    public Student(String name, String sex, String stuNo) {
        this.name = name;
        this.sex = sex;
        this.stuNo = stuNo;
    }

    public void speak(String msg) {
        System.out.println(msg);
    }
    public int calculate(int a, int b) {
        return a + b;
    }
}

public class Main {
    // （2）创建主类：创建一个对象：名叫“王明”，年龄19岁，性别“男”，学号00001；让该对象调用成员方法：说出“你好！”，计算19+20的值
    public static void main(String[] args) {
        Student student = new Student("王明", "男", "00001");
        student.speak("你好！");
        student.calculate(19, 20);
    }
}