适配器模式

适配器模式主要是为了在不能改变现有类的情况下，将一个类转换成另一种类，让他可以适应一个通用的接口

public interface Printable {
    void printSth();
}

public class Printer implements Printable {
    @Override
    public void printSth() {
        System.out.println("I can print text");
    }
}

public class Photogragher {
    public void printPhoto(){
        System.out.println("I can print photogragh");
    }
}

public class PhotogragherAdapter implements Printable {
    private Photogragher p = null;
    
    public PhotogragherAdapter(Photogragher p) {
        this.p = p;
    }
    
    @Override
    public void printSth() {
        p.printPhoto();
    }
}

public class Client {
    public static void test(Printable p) {
        p.printSth();
    }
    
    public static void main(String[] args) {
        Printable printer = new Printer();
        Photogragher photogragher = new Photogragher();
        PhotogragherAdapter adapter = new PhotogragherAdapter(photogragher);
        test(printer);
        test(adapter);
    }
}

此处的目的就是在不修改Photogragher类的前提下让Photographer也能适用于 Clinet.test() 方法