设计模式-适配器模式之登录

正常的登录功能【简化】：

1、设置接口返回：

package com.jdwa.adapter;

public class ResultMsg {
    private int code;
    private String msg;
    private Object data;

    public ResultMsg(int code, String msg, Object data) {
        this.code = code;
        this.msg = msg;
        this.data = data;
    }

    public int getCode() {
        return code;
    }

    public void setCode(int code) {
        this.code = code;
    }

    public String getMsg() {
        return msg;
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }

    public Object getData() {
        return data;
    }

    public void setData(Object data) {
        this.data = data;
    }
}

2、登录逻辑：

package com.jdwa.adapter;

public class PassportService {

    public ResultMsg regist(String username,String password){
    System.out.println("registSucess!");
        return new ResultMsg(200,"regist Success!",new Member());
    }

    public ResultMsg login(String username,String password){
        System.out.println("username:"+username+";password:"+password);
        return null;
    }
}

使用适配器

为了遵循开闭原则，老系统的代码不做修改，下面开始重构：
1、创建Member类：

package com.jdwa.adapter;

public class Member {
    private String username;
    private String password;
    private String mid;
    private String info;

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getMid() {
        return mid;
    }

    public void setMid(String mid) {
        this.mid = mid;
    }

    public String getInfo() {
        return info;
    }

    public void setInfo(String info) {
        this.info = info;
    }
}

2、创建Target角色IPassportForThird:

package com.jdwa.adapter;

public interface IPassportForThird {
    ResultMsg loginForQQ(String openId);
    ResultMsg loginForWeChat(String openId);
    ResultMsg loginForToken(String token);
    ResultMsg loginForTelPhone(String phone,String code);
}

3、创建适配器角色兼容，继承原来的逻辑

package com.jdwa.adapter;

public class PassportForThirdAdapter extends PassportService implements IPassportForThird{

    @Override
    public ResultMsg loginForQQ(String openId) {
        System.out.println("loginForQQ:"+openId);
        return null;
    }

    @Override
    public ResultMsg loginForWeChat(String openId) {
        System.out.println("loginForWeChat:"+openId);
        return null;
    }

    @Override
    public ResultMsg loginForToken(String token) {
        System.out.println("loginForToken:"+token);
        return null;
    }

    @Override
    public ResultMsg loginForTelPhone(String phone, String code) {
        System.out.println("loginForTelPhone:"+phone+"-->"+code);
        return null;
    }
    
}

Client:

package com.jdwa.adapter;

public class Client {
    public static void main(String[] args) {
        PassportForThirdAdapter adapter = new PassportForThirdAdapter();
        adapter.login("czz","123");
        adapter.loginForQQ("QQ_OPenId");
        adapter.loginForTelPhone("phoneNum","457856");
        adapter.loginForToken("token");
        adapter.loginForWeChat("wechat");
    }
}

username:czz;password:123
loginForQQ:QQ_OPenId
loginForTelPhone:phoneNum-->457856
loginForToken:token
loginForWeChat:wechat

优化使用适配器的代码

通过创建不同的Adapter来实现
1、创建ILoginAdapter接口,规范所有登录适配器的接口

package com.jdwa.adapterv2;

public interface ILoginAdapter {
    boolean support(Object adapter);
    ResultMsg login(String id,Object adapter);
}

2、创建一个AbstractorAdapter继承PassportService原有的功能，同时实现ILoginAdapter

package com.jdwa.adapterv2;

public abstract class  AbstractAdapter  extends PassportService implements ILoginAdapter {
    protected ResultMsg loginForRegist(String datainfo,String msg,boolean support){
        System.out.println("*********************************************");
        if (!support) new ResultMsg(500,"服务器错误","请联系管理人员");;
        System.out.println("通过"+msg+"登陆成功："+datainfo);
        return new ResultMsg(200,"通过"+msg+"登录成功","model信息");
    }
}

3、创建QQ等登录适配器：篇幅有限，就只举QQ和手机两个例子了

package com.jdwa.adapterv2;

public class LoginForQQAdapter extends AbstractAdapter {
    @Override
    public boolean support(Object adapter) {
        return adapter instanceof LoginForQQAdapter;
    }

    @Override
    public ResultMsg login(String openId, Object adapter) {
        return super.loginForRegist(openId,"QQ",support(adapter));
    }
}

package com.jdwa.adapterv2;

public class LoginForTelAdapter extends AbstractAdapter {
    @Override
    public boolean support(Object adapter) {
        return adapter instanceof LoginForTelAdapter;
    }

    @Override
    public ResultMsg login(String openId, Object adapter) {
        return super.loginForRegist(openId,"手机",support(adapter));
    }
}

4、创建适配器PassportForThirdAdapter:

package com.jdwa.adapterv2;


public class PassportForThirdAdapter implements IPassportForThird{
    @Override
    public ResultMsg


    loginForQQ(String openId) {
        return processLogin(openId,LoginForQQAdapter.class);
    }

    @Override
    public ResultMsg loginForWeChat(String openId) {
        return processLogin(openId,LoginForWechatAdapter.class);
    }

    @Override
    public ResultMsg loginForToken(String token) {
        return processLogin(token,LoginForTokenAdapter.class);
    }

    @Override
    public ResultMsg loginForTelPhone(String phone, String code) {
        return processLogin(phone+"->"+code,LoginForTelAdapter.class);
    }

    private ResultMsg processLogin(String id , Class<? extends ILoginAdapter> clazz){
        try {
            ILoginAdapter adapter = clazz.newInstance();
            return adapter.login(id,adapter);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }
}

5、测试

package com.jdwa.adapterv2;

public class Client {
    public static void main(String[] args) {
        IPassportForThird adapter = new PassportForThirdAdapter();
        adapter.loginForQQ("45785678");
        adapter.loginForTelPhone("15112345678","12345678");
    }
}

*********************************************
通过QQ登陆成功：45785678
*********************************************
通过手机登陆成功：15112345678->12345678

类图：

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