java(继承+封装+多态)编程:定义一个人类(Person)，包括属性:姓名、性别、年龄、国籍；包括的方法:吃饭、睡觉，工作

(继承+封装)编程:定义一个人类(Person)，包括属性:姓名、性别、年龄、国籍；
                                    包括的方法:吃饭、睡觉，工作
(1)根据人类，定义一个学生子类，增加属性:学校、学号；重写工作方法(实现内容为学习)
(2)根据人类，定义一个工人类，增加属性：单位、工龄；重写工作方法
(3)根据学生类，定义一个学生干部类（StudentLeader）,增加属性:职务；增加方法:开会
(4)定义一个测试类，分别创建上述3类具体人物的对象并将信息打印在控制台上.

public class Person {
    private String name;
    private String sex;
    private int age;
    private String nationality;

    public Person() {
    }

    public Person(String name, String sex, int age, String nationality) {
        this.name = name;
        this.sex = sex;
        this.age = age;
        this.nationality = nationality;
    }

    public String getName() {
        return name;
    }

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

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public int getAge() {
        return age;
    }

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

    public String getNationality() {
        return nationality;
    }

    public void setNationality(String nationality) {
        this.nationality = nationality;
    }

    public void eat(){
        System.out.println("吃饭");
    }
    public void sleep(){
        System.out.println("睡觉");
    }
    public void jop(){
        System.out.println("工作");
    }

    @Override
    public String toString() {
        return "Person{" +
                "name='" + name + '\'' +
                ", sex='" + sex + '\'' +
                ", age=" + age +
                ", nationality='" + nationality + '\'' +
                '}';
    }
}
class StuentPerson extends Person{
    private String school;
    private int id;

    public StuentPerson() {
    }

    public StuentPerson(String school, int id) {
        this.school = school;
        this.id = id;
    }

    public StuentPerson(String name, String sex, int age, String nationality, String school, int id) {
        super(name, sex, age, nationality);
        this.school = school;
        this.id = id;
    }

    public String getSchool() {
        return school;
    }

    public void setSchool(String school) {
        this.school = school;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    @Override
    public void jop() {
        System.out.println("学生学习");
    }
}
class WorkerPenson extends Person{
    private String workplace;
    private int seniority;

    public WorkerPenson() {
    }
    public WorkerPenson(String workplace, int seniority) {
        this.workplace = workplace;//单位
        this.seniority = seniority;//工龄
    }

    public WorkerPenson(String name, String sex, int age, String nationality, String workplace, int seniority) {
        super(name, sex, age, nationality);
        this.workplace = workplace;
        this.seniority = seniority;
    }

    public String getWorkplace() {
        return workplace;
    }

    public void setWorkplace(String workplace) {
        this.workplace = workplace;
    }

    public int getSeniority() {
        return seniority;
    }

    public void setSeniority(int seniority) {
        this.seniority = seniority;
    }

    @Override
    public void jop() {
        System.out.println("工人工作");
    }
}
class StudentLeader extends StuentPerson{
    private String post;//职务

    public StudentLeader() {
    }
    public StudentLeader(String post) {
        this.post = post;
    }

    public StudentLeader(String school, int id, String post) {
        super(school, id);
        this.post = post;
    }

    public StudentLeader(String name, String sex, int age, String nationality, String school, int id, String post) {
        super(name, sex, age, nationality, school, id);
        this.post = post;
    }

    public String getPost() {
        return post;
    }

    public void setPost(String post) {
        this.post = post;
    }

    public void meeting(){
        System.out.println("学生干部开会");
    }

}
class PensonTest{
    public static void main(String[] args) {
        StuentPerson stuentPerson = new StuentPerson("张三","男",21,"中国","四川工业",101);
        stuentPerson.jop();
        System.out.println(stuentPerson.getName()+stuentPerson.getSex()+stuentPerson.getAge()+stuentPerson.getNationality()+stuentPerson.getSchool()+stuentPerson.getId());

        WorkerPenson workerPenson = new WorkerPenson("李四","女",32,"中国","中信银行",3);
        workerPenson.jop();
        System.out.println(workerPenson.getName()+workerPenson.getSex()+workerPenson.getAge()+workerPenson.getNationality()+workerPenson.getWorkplace()+workerPenson.getSeniority());

        StudentLeader studentLeader = new StudentLeader("学生会主席");
        studentLeader.jop();
        studentLeader.meeting();
        System.out.println(stuentPerson.getName()+stuentPerson.getSex()+stuentPerson.getAge()+stuentPerson.getNationality()+stuentPerson.getSchool()+stuentPerson.getId()+studentLeader.getPost());

        stuentPerson.eat();
        stuentPerson.sleep();

        workerPenson.eat();
        workerPenson.sleep();

        studentLeader.eat();
        studentLeader.sleep();


    }
}

(多态)在上一个题目的基础上，定义一个Person类型的数组，存储多个不同类型的子类型对象，
(1)统计并打印输出数组中所有学生干部的个数
(2)打印输出所有学生的信息

public abstract class Person {
    private String name;
    private String sex;
    private int age;
    private String nationality;

    public Person() {
    }

    public Person(String name, String sex, int age, String nationality) {
        this.name = name;
        this.sex = sex;
        this.age = age;
        this.nationality = nationality;
    }

    public String getName() {
        return name;
    }

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

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public int getAge() {
        return age;
    }

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

    public String getNationality() {
        return nationality;
    }

    public void setNationality(String nationality) {
        this.nationality = nationality;
    }

    public void eat() {
        System.out.println("吃饭");
    }

    public void sleep() {
        System.out.println("睡觉");
    }

    public abstract void jop();

    @Override
    public String toString() {
        return "姓名='" + name + '\'' +
                ", 性别='" + sex + '\'' +
                ", 年龄=" + age +
                ", 国籍='" + nationality;
    }
}

class StudentPerson extends Person {
    private String school;
    private int id;

    public StudentPerson() {
    }

    public StudentPerson(String school, int id) {
        this.school = school;
        this.id = id;
    }

    public StudentPerson(String name, String sex, int age, String nationality, String school, int id) {
        super(name, sex, age, nationality);
        this.school = school;
        this.id = id;
    }

    public String getSchool() {
        return school;
    }

    public void setSchool(String school) {
        this.school = school;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    @Override
    public void jop() {
        System.out.println("学生学习");
    }

    @Override
    public String toString() {
        return super.toString()+" ,学校："+school+" ,学号："+id;
    }
}

class WorkerPenson extends Person {
    private String workplace;
    private int seniority;

    public WorkerPenson() {
    }

    public WorkerPenson(String workplace, int seniority) {
        this.workplace = workplace;//单位
        this.seniority = seniority;//工龄
    }

    public WorkerPenson(String name, String sex, int age, String nationality, String workplace, int seniority) {
        super(name, sex, age, nationality);
        this.workplace = workplace;
        this.seniority = seniority;
    }

    public String getWorkplace() {
        return workplace;
    }

    public void setWorkplace(String workplace) {
        this.workplace = workplace;
    }

    public int getSeniority() {
        return seniority;
    }

    public void setSeniority(int seniority) {
        this.seniority = seniority;
    }

    @Override
    public void jop() {
        System.out.println("工人工作");
    }

    @Override
    public String toString() {
        return super.toString()+" ,单位："+workplace+" ,工龄："+seniority;
    }
}

class StudentLeader extends StudentPerson {
    private String post;//职务

    public StudentLeader() {
    }

    public StudentLeader(String post) {
        this.post = post;
    }

    public StudentLeader(String school, int id, String post) {
        super(school, id);
        this.post = post;
    }

    public StudentLeader(String name, String sex, int age, String nationality, String school, int id, String post) {
        super(name, sex, age, nationality, school, id);
        this.post = post;
    }

    public String getPost() {
        return post;
    }

    public void setPost(String post) {
        this.post = post;
    }

    public void meeting() {
        System.out.println("学生干部开会");
    }

    @Override
    public String toString() {
        return super.toString()+"职务："+post;
    }
}

class PersonTest {
    public static void main(String[] args) {
        WorkerPenson worker = new WorkerPenson("张三","男",23,"中国","中国石油",2);
        Person worker1 = new WorkerPenson("李四","男",30,"中国","中国联通",6);

        StudentPerson studentPerson = new StudentPerson("马瑞","女",30,"中国","四川工业",101);
        Person studentPerson1 = new StudentPerson("杰克","女",23,"中国","西南财经",201);

        StudentLeader studentLeader = new StudentLeader("汤姆","男",34,"中国","四川工业",108,"文体部");
        Person studentLeader1 = new StudentLeader("肉丝","男",19,"中国","西南",112,"外联部");
        Person studentLeader2 = new StudentLeader("白菜","男",20,"中国","西南",333,"全媒体");
        Person[] person = new Person[]{worker,worker1,studentPerson,studentPerson1,studentLeader,studentLeader1,studentLeader2};

        int count=0;
        for (int i=0;i