Java基础巩固抽象类与接口详解

abstract class Shape{
   
    public abstract void draw();//抽象方法
}

abstract class Shape{
   
    public abstract void draw();//抽象方法
}
abstract class A extends Shape{  //当一个抽象类A继承抽象类Shape时，可以不重写抽象类Shape中的方法
    public abstract void func();
}
class B extends A{  //出来混迟早得还，父类没有重写  你全写
    @Override
    public void draw() {
    }
    @Override
    public void func() {
    }
}
class Circle extends Shape {  //普通类继承了抽象类（内有抽象方法），这里报错，  必须重写Shap类当中的抽象个方法
    @Override
    public void draw() {
        System.out.println("⚪");
    }
}
class Rect extends Shape {
    @Override
    public void draw() {
        System.out.println("♦");
    }
}
class Triangle extends Shape {
    @Override
    public void draw() {
        System.out.println("?");
    }
}
public class Testdemo {
    public static void drawMap(Shape shape){
        shape.draw();
    }
    public static void main(String[] args) {
        //Shape shape = new Shape();    //1、抽象类不能进行实例化
        Circle circle = new Circle();
        Rect rect = new Rect();
        Triangle triangle = new Triangle();
        drawMap(circle);
        drawMap(rect);
        drawMap(triangle);
    }
    //输出结果:
    //就是按顺序输出三种图形
}

interface IShape{
   
    void draw();
}

class Circle implements IShape {   //一个普通的类可以通过implemengts来实现这个接口  另外:重写抽象方法
    @Override
    public void draw() {
        System.out.println("⚪");
    }
}

interface IShape{
   
    void draw();
}
class Circle implements IShape {   //一个普通的类可以通过implemengts来实现这个接口  另外:重写抽象方法
    @Override
    public void draw() {
        System.out.println("⚪");
    }
}
class Rect implements IShape {
    @Override
    public void draw() {
        System.out.println("♦");
    }
}
class Triangle implements IShape {
    @Override
    public void draw() {
        System.out.println("?");
    }
}
  
public class Test {
        public static void drawMap(IShape shape){
            shape.draw();
        }
        public static void main(String[] args) {
            //Shape shape = new Shape();    //1、抽象类不能进行实例化
            Circle circle = new Circle();
            Rect rect = new Rect();
            Triangle triangle = new Triangle();
            drawMap(circle);
            drawMap(rect);
            drawMap(triangle);
        }
        //IShape iShape = new IShape();  //接口不能实例化
        
}

class Animal {
    public String name;
    public Animal(String name) {
        this.name = name;
    }
    public void eat(){
        System.out.println("吃饭饭！");
    }
    // 飞  跑  游泳    布恩那个把这些操作写在这里
}
interface IFlying{
    void fly();
}
interface IRunning{
    void run();
}
interface ISwimming{
    void swim();
}
class Cat extends Animal implements IRunning{
    public Cat(String name) {
        super(name);
    }
    @Override
    public void run() {
        System.out.println(this.name+"is cat 正在跑！");
    }
}
//狗  继承了Animal实现了 跑和游泳接口    先继承后实现   需要重写两接口的方法
class Dog extends Animal implements IRunning,ISwimming{
    public Dog(String name){
        super(name);
    }
    @Override
    public void run() {
        System.out.println(this.name+"is dog 正在跑！");
    }
    @Override
    public void swim() {
        System.out.println(this.name+"正在游泳！");
    }
}
class Robot implements IRunning{
    @Override
    public void run() {
        System.out.println("我是机器人，我在跑！");
    }
}
class Duck extends Animal implements IRunning,ISwimming,IFlying{
    public Duck(String name) {
        super(name);
    }
    @Override
    public void fly() {
        System.out.println(this.name+"鸭子正在飞！");
    }
    @Override
    public void run() {
        System.out.println(this.name+"鸭子正在跑！");
    }
    @Override
    public void swim() {
        System.out.println(this.name+"鸭子正在游泳！");
    }
}
public class TestDemo1 {
    public static void walk(IRunning iRunning){
        iRunning.run();
    }
    public static void fly(IFlying iFlying){
        iFlying.fly();
    }
    public static void swim(ISwimming iSwimming){
        iSwimming.swim();
    }
    public static void main(String[] args) { 
        //swim(new Dog("小狗"));
        Duck duck = new Duck("小鸭子");
        swim(duck);
        walk(duck);
        fly(duck);
    }
    public static void main2(String[] args) {
        walk(new Cat("mimi"));
        walk(new Dog("mimi2"));
        walk(new Robot());
    }
    public static void main1(String[] args) {
        Animal animal = new Cat("mimi");
        Animal animal2 = new Dog("mimi2");
        IRunning iRunning = new Cat("mimi");
        IRunning iRunning2 = new Dog("mimi2");
        ISwimming iSwimming2 = new Dog("mimi2");
    }
}

interface C extends A,B{
    void funcC();
}
class AA implements C{    //类和接口之间是implements  那么接口与接口之间呢----extends[扩展]
    @Override
    public void funcC() {
        System.out.println("funcC");
    }
    @Override
    public void funcA() {
    }
    @Override
    public void funcB() {
    }
}

import java.util.Arrays;
class Student implements Comparable<Student>{
    public String name;
    public int age;
    public double score;
    public Student(String name, int age, double score) {
        this.name = name;
        this.age = age;
        this.score = score;
    }
    @Override
    public String toString() {
        return "Student{" +
                "name='" + name + '\'' +
                ", age=" + age +
                ", score=" + score +
                '}';
    }
    @Override
    public int compareTo(Student o) {
      
        //return this.name.compareTo(o.name);//姓名比较
        //return this.age-o.age;//年龄比较
        return (int) (this.score-o.score);//分数比较
    }
}
public class Test {
    public static void main(String[] args) {
        Student student1 = new Student("zhangsan",98,78.9);
        Student student2 = new Student("lisi",38,18.9);
        System.out.println(student1.compareTo(student2));
    }
    public static void main1(String[] args) {
        Student[] students = new Student[3];
        students[0] = new Student("zhangsan",98,78.9);
        students[1] = new Student("lisi",38,18.9);
        students[2] = new Student("abc",78,88.9);
        Arrays.sort(students);
        System.out.println(Arrays.toString(students));
    }
}