week3

点击这个一键复制代码

观前须知

观看方法，前半为答案，后半为解析（全部题目都为跳进度，所有解析你们应该也看不懂，仅为爱学习的提供，实在不懂可以来问奶糖）

所有####里需要自己修改的都是为了避免数据雷同

第一题

class名为Student

public class Student {
    String name = "张三";
    int age;
    public Student() {
        age = 18;
    }
    public static void main(String args[]) {
        Student ### = new Student();
        System.out.println("姓名：" + ###.name + ",年龄：" + ###.age);
    }

}

将所有‘###’换成自己的变量（改个名字就行）。为了避免重复。

第二题

class名为PeopleDemo

class People {
    public String name;
    People(String name) {
        this.name = name;
    }
}
class Student extends People {
    String stuID;
    Student(String name, String stuID) {
        super(name);
        this.stuID = stuID;
    }
}
public class PeopleDemo {
    public static void main(String arg[]) {
        Student student = new Student("张三", "20080601");
        System.out.println("姓名：" + student.name + "，学号：" + student.stuID);
    }
}

解析版

class People {//创建父类
    public String name;//名字变量（实例变量）
    People(String name) {//构造方法
        this.name = name;//名字初始化
    }
}
class Student extends People {//创建子类，继承父类的所有可见变量方法。
    String stuID;//id变量
    Student(String name, String stuID) {//构造方法。
        super(name);//将name带到父类，执行构造方法
        this.stuID = stuID;
    }
}
public class PeopleDemo {
    public static void main(String arg[]) {
        Student student = new Student("张三", "20080601");
        System.out.println("姓名：" + student.name + "，学号：" + student.stuID);
    }
}

第3题

class名为Ex3_3

public class Ex3_3 {
    public static void main(String[] args) {
        Student s1=new Student(##学号##,"##名字##","##性别##",##年龄##);
        Student s2=new Student(##学号##,"##名字##","##性别##",##年龄##);
        System.out.println("学号:"+s1.show_No()+"\t"+"姓名:"+s1.show_Name()+"\t"+"性别:"+s1.show_Sex()+"\t"+"年龄:"+s1.show_Age());
        System.out.println("学号:"+s2.show_No()+"\t"+"姓名:"+s2.show_Name()+"\t"+"性别:"+s2.show_Sex()+"\t"+"年龄:"+s2.show_Age());
        s1.modifyAge(##年龄##);
        System.out.println("修改后");
        System.out.println("学号:"+s1.show_No()+"\t"+"姓名:"+s1.show_Name()+"\t"+"性别:"+s1.show_Sex()+"\t"+"年龄:"+s1.show_Age());
    }
}
class Student{
    int s_No;
    String s_Name;
    String s_Sex;
    int s_Age;
    public String show_Name() {
        return s_Name;
    }
    public int show_No() {
        return s_No;
    }
    public String show_Sex() {
        return s_Sex;
    }
    public int show_Age() {
        return s_Age;
    }
    public void modifyAge(int s_Age) {
        this.s_Age = s_Age;
    }
    public Student(int s_No,String s_Name,String s_Sex,int s_Age) {
        this.s_No = s_No;
        this.s_Name = s_Name;
        this.s_Sex=s_Sex;
        this.s_Age=s_Age;
    }
}

将##内的替换成自己的数据，输入的类型就是里面的文字提示

解析版

public class Ex3_3 {
    public static void main(String[] args) {
        Student s1=new Student(##学号##,"##名字##","##性别##",##年龄##);
        Student s2=new Student(##学号##,"##名字##","##性别##",##年龄##);//初始化
        System.out.println("学号:"+s1.show_No()+"\t"+"姓名:"+s1.show_Name()+"\t"+"性别:"+s1.show_Sex()+"\t"+"年龄:"+s1.show_Age());
        System.out.println("学号:"+s2.show_No()+"\t"+"姓名:"+s2.show_Name()+"\t"+"性别:"+s2.show_Sex()+"\t"+"年龄:"+s2.show_Age());//输出
        s1.modifyAge(##年龄##);//修改
        System.out.println("修改后");
        System.out.println("学号:"+s1.show_No()+"\t"+"姓名:"+s1.show_Name()+"\t"+"性别:"+s1.show_Sex()+"\t"+"年龄:"+s1.show_Age());
    }
}
class Student{
    int s_No;
    String s_Name;
    String s_Sex;
    int s_Age;//四种变量
    public String show_Name() {
        return s_Name;
    }
    public int show_No() {
        return s_No;
    }
    public String show_Sex() {
        return s_Sex;
    }
    public int show_Age() {//四种输出变量
        return s_Age;
    }
    public void modifyAge(int s_Age) {//修改age
        this.s_Age = s_Age;
    }
    public Student(int s_No,String s_Name,String s_Sex,int s_Age) {
        this.s_No = s_No;
        this.s_Name = s_Name;
        this.s_Sex=s_Sex;
        this.s_Age=s_Age;//初始化
    }
}