인터페이스

package com.study.javastudy.study;

public interface TV {
    public int MIN_VOLUME = 0;
    public int MAX_VOLUME = 100;
    
    public void turnOn();
    public void turnOff();
    public void changeVolume(int volume);
    public void changeChannel(int channel);
}

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package com.study.javastudy.study;

public class LedTV implements TV{
    @Override
    public void turnOn() {
        System.out.println("켜다");
    }

    @Override
    public void turnOff() {
        System.out.println("끄다");
    }

    @Override
    public void changeVolume(int volume) {
        System.out.println("볼륨을 조정하다");
    }

    @Override
    public void changeChannel(int channel) {
        System.out.println("채널을 지정하다");
    }
}

package com.study.javastudy.study;

public class LedExam {
    public static void main(String[] args) {
        TV tv = new LedTV();
        tv.turnOn(); // 켜다
        tv.changeChannel(8); // 채널을 지정하다
        tv.changeVolume(39); // 볼륨을 조정하다
        tv.turnOff(); // 끄다
    }
}

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