Helpful examples of encapsulation and inheritance in Java

Java basic tutorialThe column introduces helpful cases of encapsulation and inheritance in Java

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1. Code and renderings

1. Encapsulation

Case: Requirements Description
Use encapsulation to implement the penguin class of the electronic pet system to correctly input the health value and intimacy
Ensure the validity of the health value (0 -100), otherwise take the default value of 60
to ensure the effectiveness of intimacy (0-100), otherwise take the default value of 60
The code is as follows (example):

package work1;

public class Dog {
    private String name;
    private String sex;
    private int love;

    public String getName() {
        return name;
    }

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

    public String getSex() {
        return sex;
    }

    public void setSex(int sex) {
        if(sex==1){
            this.sex = "Q仔";
        }else{
            this.sex = "Q妹";
        }

    }

    public int getLove() {
        return love;
    }

    public void setLove(int love) {
        if(love>=0&&love<pre class="brush:php;toolbar:false">package work1;

public class Penguin {
    private String name;
    private String sex;
    private int health;

    public String getName() {
        return name;
    }

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

    public String getSex() {
        return sex;
    }

    public void setSex(int sex) {
        if(sex==1){
            this.sex = "Q仔";
        }else{
            this.sex = "Q妹";
        }

    }

    public int getHealth() {
        return health;
    }

    public void setHealth(int health) {
        if(health>=0&&health<pre class="brush:php;toolbar:false">package work1;

import java.util.Scanner;

public class Test1 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("欢迎您来到宠物店! \n 请输入要领养宠物的名字：");
        String name = sc.next();
        System.out.println("请选择要领养的宠物类型：（1.狗狗  2.企鹅）");
        int i = sc.nextInt();
        if(i==1){//狗狗
            Dog dog = new Dog();
            dog.setName(name);
            System.out.println("请选择狗狗的性别：(1.Q仔  2.Q妹)");
            dog.setSex(sc.nextInt());
            System.out.println("请输入狗狗的亲密度（1~100之间）：");
            dog.setLove(sc.nextInt());

            System.out.println("宠物的自白：\n 我的名字叫"+name+",健康值是"+0+",和主人的" +
                    "亲密度是"+dog.getLove()+",我的性别是"+dog.getSex());
        }else {//企鹅
            Penguin p = new Penguin();
            p.setName(name);
            System.out.println("请选择企鹅的性别：(1.Q仔  2.Q妹)");
             p.setSex(sc.nextInt());
            System.out.println("请输入企鹅的健康值（1~100之间）：");
             p.setHealth(sc.nextInt());
            System.out.println("宠物的自白：\n 我的名字叫"+name+",健康值是"+p.getHealth()+",和主人的" +
                    "亲密度是"+0+",我的性别是"+p.getSex());
        }

    }
}

2. Inheritance

Case: Use inheritance to optimize the electronic pet system, extract the parent class, create a subclass, and use super in the subclass to call the parent class constructor.
The code is as follows (example):

package work3;

public class Dog extends Pet {
    @Override
    public void show() {
        System.out.println("宠物的自白：\n 我的名字叫"+this.getName()+",健康值是"+0+",和主人的" +
                "亲密度是"+this.getLove()+",我的性别是"+this.getSex());
    }

    private int love;

    public Dog(String name, int sex, int love) {
        super(name, sex);
        this.love = love;
    }

    public int getLove() {
        return love;
    }

    public void setLove(int love) {
        if(love>=0&&love<pre class="brush:php;toolbar:false">package work3;

public class Penguin extends Pet {

    @Override
    public void show() {
        System.out.println("宠物的自白：\n 我的名字叫"+this.getName()+",健康值是"+this.getHealth()+",和主人的" +
                "亲密度是"+0+",我的性别是"+this.getSex());
    }
    private int health;

    public Penguin(String name, int sex, int health) {
        super(name, sex);
        this.health = health;
    }

    public int getHealth() {
        return health;
    }

    public void setHealth(int health) {
        if(health>=0&&health<pre class="brush:php;toolbar:false">package work3;

public class Pet {
    private String name;
    private String sex;

    public void show(){

    }

    public Pet(String name, int sex) {
        this.name = name;
        if(sex==1){
            this.sex = "Q仔";
        }else{
            this.sex = "Q妹";
        }
    }

    public String getName() {
        return name;
    }

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

    public String getSex() {
        return sex;
    }

    public void setSex(int sex) {
        if(sex==1){
            this.sex = "Q仔";
        }else{
            this.sex = "Q妹";
        }

    }
}

package work3;

import java.util.Scanner;

import static java.lang.System.out;

public class Test2 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        out.println("欢迎您来到宠物店! \n 请输入要领养宠物的名字：");
        String name = sc.next();
        out.println("请选择要领养的宠物类型：（1.狗狗  2.企鹅）");
        int i = sc.nextInt();
        if (i==1){//狗狗
            out.println("请选择狗狗的性别：(1.Q仔  2.Q妹)");
            int sex=sc.nextInt();
            out.println("请输入狗狗的亲密度（1~100之间）：");
            Dog dog = new Dog(name, sex, sc.nextInt());
            dog.show();
        }else {//企鹅
            out.println("请选择企鹅的性别：(1.Q仔  2.Q妹)");
            int sex=sc.nextInt();
            out.println("请输入企鹅的健康值（1~100之间）：");
            Penguin p = new Penguin(name, sex, sc.nextInt());
            p.show();
        }
    }
}

##Summary

The above is the content of the encapsulation and inheritance case, which mainly uses Encapsulation and inheritance methods.

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