Java中如何抽象对象行为？OOP方法分享

abstract class Animal {
    abstract void makeSound(); // 行为抽象：发出声音

    void sleep() {
        System.out.println("Animal is sleeping");
    }
}

class Dog extends Animal {
    void makeSound() {
        System.out.println("Woof!");
    }
}

class Cat extends Animal {
    void makeSound() {
        System.out.println("Meow!");
    }
}

interface Flyable {
    void fly();
}

class Bird extends Animal implements Flyable {
    public void makeSound() {
        System.out.println("Chirp!");
    }

    public void fly() {
        System.out.println("Bird is flying.");
    }
}

interface MoveStrategy {
    void move();
}

class Walk implements MoveStrategy {
    public void move() {
        System.out.println("Walking on legs");
    }
}

class Swim implements MoveStrategy {
    public void move() {
        System.out.println("Swimming in water");
    }
}

class Animal {
    private MoveStrategy moveStrategy;

    public Animal(MoveStrategy strategy) {
        this.moveStrategy = strategy;
    }

    public void performMove() {
        moveStrategy.move();
    }

    public void setMoveStrategy(MoveStrategy strategy) {
        this.moveStrategy = strategy;
    }
}