接口（听课笔记）

来源：互联网发布：单片机用什么编程编辑：程序博客网时间：2024/05/16 17:50

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接口的基本语法：使用interface定义；接口中的方法都是抽象方法；方法的权限都是public;一个类可以实现多个接口；一个接口可以继承多个接口；

接口是更加极端的抽象类：

抽象类是可以有私有方法或私有变量，非抽象类子类必须实现其抽象父类的所有抽象方法（非抽象方法可以不用实现）

接口权限是public，里面不能有私有的方法或变量，实现接口的一定要实现接口里定义的所有方法
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//USB接口
interface USB{
public void read{};
public void write{];
}
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//Wifi接口

interface Wifi{
public void open();
public viod close();
}
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//手机实现USB与Wifi接口
class Phone implements USB,Wifi{
public void read(){
  System.out.println("read");
}
public viod write(){
  System.out.println("write");
}
public viod open(){
  System.out.println("Wifi open");
}
public void close(){
  System.out.println("Wifi close");
}
}
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//测试
class Test{
public satatic void main(String [] args){
  USBphone phone = new Usbphone();
  USB usb = phone;
  usb.read();
  usb.write();
  Wifi wifi = phone;
  wifi.open();
  wifi.close();
}
}
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interface A{
public void funA();
}
interface B{
public void funB();

}

//C接口继承了A,B两个接口（父类与子类之间只能实现单继承，但接口可以实现多继承）
interface C extends A,B{
public void funC();
}
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