设计模式——适配器模式

适配器模式也叫做包装模式；就是把内部结构包装（适配）成用户期待的格式，使得可以兼容使用

通过继承方式使用适配器模式

/**
 * @author maikec
 * @date 2019/5/9
 */
public interface Print {
    /**
     * 打印带括号的消息
     */
    void printParen();

    /**
     * 打印带*号的消息
     */
    void printAster();
}

/**
 * 实际使用中的类
 * @author maikec
 * @date 2019/5/9
 */
public class Banner {
    private final String msg;
    public Banner(String msg){
        this.msg = msg;
    }
    public void showWithParen(){
        System.out.println( "(" + msg + ")" );
    }
    public void showWithAster(){
        System.out.println( "*" + msg + "*" );
    }
}

/**
 * @author maikec
 * @date 2019/5/9
 */
public class PrintBannerAdapter extends Banner implements Print {

    public PrintBannerAdapter(String msg) {
        super( msg );
    }

    @Override
    public void printParen() {
        showWithParen();
    }

    @Override
    public void printAster() {
        showWithAster();
    }
}

/**
 * @author maikec
 * @date 2019/5/9
 */
public class AdapterExtendDemo {
    public static void main(String[] args) {
        Print print = new PrintBannerAdapter( "hello adapter" );
        print.printAster(  );
        print.printParen();
    }
}

通过引用使用适配器模式

/**
 * 需求
 * @author maikec
 * @date 2019/5/9
 */
public abstract class Print {
    /**
     * 打印带括号的消息
     */
    public abstract void printParen();

    /**
     * 打印带*号的消息
     */
    public abstract void printAster();

    public void i(){

    }
}

/**
 * 实际使用中的类
 * @author maikec
 * @date 2019/5/9
 */
public class Banner {
    private final String msg;
    public Banner(String msg){
        this.msg = msg;
    }
    public void showWithParen(){
        System.out.println( "(" + msg + ")" );
    }
    public void showWithAster(){
        System.out.println( "*" + msg + "*" );
    }
}

/**
 * @author maikec
 * @date 2019/5/9
 */
public class PrintBannerAdapter extends Print {
    private Banner banner;

    public PrintBannerAdapter(Banner banner){
        this.banner = banner;
    }
    @Override
    public void printParen() {
        banner.showWithParen();
    }

    @Override
    public void printAster() {
        banner.showWithAster();
    }
}

/**
 * @author maikec
 * @date 2019/5/9
 */
public class AdapterReferenceDemo {
    public static void main(String[] args) {
        Print print = new PrintBannerAdapter( new Banner( "Hello Adapter" ) );
        print.printAster();
        print.printParen();
    }
}

附录

zh.wikipedia.org/wiki/适配器模式 维基关于适配器模式
github.com/maikec/patt… 个人GitHub设计模式案例

声明

引用该文档请注明出处