前段时间有人给我建议，Retrofit应该加上同意错误处理以及返回Call的包装，今天抽时间就在这里简单的记录记录。。。。。

关于Retrofit前面的东西就不说了，主要是对请求的操作统一做个处理。去前章理理思路

• 我先拿俩个串看下

//串①
{code:200,msg:null,data:{userId:1,userName:"aa",fullName:"富民燃气管理员",companyId:1,companyName:"虎门能源",mobileModules:[]}}


//串②
{code:200,msg:null,data:{company:{storeName:null,storeCode:null,saleDate:"2018-01-25",todayOrderNum:957,todayOrderBottleNum:1170,todayTotalAmount:117642,yesterdayGrowthOrderNum:-54,yesterdayGrowthOrderBottleNum:-128,yesterdayGrowthTotalAmount:-22203,saleDetailInfos:[{materialTypeName:"15KG",orderNum:764,orderBottleNum:948,totalAmount:97366},{materialTypeName:"50KG",orderNum:21,orderBottleNum:39,totalAmount:12978},{materialTypeName:"5KG",orderNum:172,orderBottleNum:183,totalAmount:7298}]},stores:[{storeName:"龙眼站",storeCode:"1010",saleDate:"2018-01-25",todayOrderNum:67,todayOrderBottleNum:75,todayTotalAmount:6567,yesterdayGrowthOrderNum:0,yesterdayGrowthOrderBottleNum:0,yesterdayGrowthTotalAmount:0,saleDetailInfos:[{materialTypeName:"15KG",orderNum:45,orderBottleNum:51,totalAmount:5295},{materialTypeName:"50KG",orderNum:1,orderBottleNum:1,totalAmount:352},{materialTypeName:"5KG",orderNum:21,orderBottleNum:23,totalAmount:920}]}]}}

在上面返回的JSON串中可以得出他们有共同的部分吧(都是请求结果返回)，那好，可以这样：

public class BaseHttpRequestBean<T> {

    /**
     * code : 200
     * msg : null
     * data : {"userId":1,"userName":"aa","fullName":"富民燃气管理员","companyId":1,"companyName":"虎门能源","mobileModules":[]}
     */
    private int code;
    private String msg;

    //定义成泛型所有公用
    private T 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 T getData() {
        return data;
    }

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

• 在对我们所有的请求结果做一个处理（预处理），以前的时候，对请求结果我们也做过处理是这样的

//添加Gson转换器
        new Retrofit.Builder().addConverterFactory(GsonConverterFactory.create(gson));

• 现在我们修改下GsonConverterFactory，可以自定义一个MyGsonConverterFactory继承Converter.Factory,只修改他responseBodyConverter和requestBodyConverter方法即可

public class MyGsonConverterFactory extends Converter.Factory {

    /**
     * Create an instance using a default {@link Gson} instance for conversion. Encoding to JSON and
     * decoding from JSON (when no charset is specified by a header) will use UTF-8.
     */
    public static MyGsonConverterFactory create() {
        return create(new Gson());
    }

    /**
     * Create an instance using {@code gson} for conversion. Encoding to JSON and
     * decoding from JSON (when no charset is specified by a header) will use UTF-8.
     */
    public static MyGsonConverterFactory create(Gson gson) {
        return new MyGsonConverterFactory(gson);
    }

    private final Gson gson;

    private MyGsonConverterFactory(Gson gson) {
        if (gson == null) throw new NullPointerException("gson == null");
        this.gson = gson;
    }

    @Override
    public Converter<ResponseBody, ?> responseBodyConverter(Type type, Annotation[] annotations,
                                                            Retrofit retrofit) {
        return new MyGsonRequestBodyConverter<>(gson, type);
    }

    @Override
    public Converter<?, RequestBody> requestBodyConverter(Type type,
                                                          Annotation[] parameterAnnotations, Annotation[] methodAnnotations, Retrofit retrofit) {
        return new MyGsonRequestBodyConverter<>(gson, type);
    }
}

MyGsonRequestBodyConverter.class

public class MyGsonRequestBodyConverter<T> implements Converter<ResponseBody, T> {

    private final Gson gson;
    private final Type type;

    MyGsonRequestBodyConverter(Gson gson, Type type) {
        this.gson = gson;
        this.type = type;
    }

    @Override
    public T convert(ResponseBody value) throws IOException {
        String response = value.string();
        BaseHttpRequestBean baseHttpRequestBean = gson.fromJson(response, BaseHttpRequestBean.class);
        //请求结果进行统一的预处理
        /**
         * 请求返回码为:
         * 200  ---  请求成功
         * 301  ---  无此用户
         * 302  ---  密码错误
         * ...  ---  未知错误
         */
        if (baseHttpRequestBean.getCode() == 301) {
            throw new ErrorApi(301);
        } else if (baseHttpRequestBean.getCode() == 302) {
            throw new ErrorApi(302);
        } else if (baseHttpRequestBean.getCode() == 200) {
            return gson.fromJson(response, type);
        } else {
            throw new ErrorApi(300);
        }
    }
}

• 统一错误返回码处理类ErrorApi

public class ErrorApi extends RuntimeException {
    public static final int USER_NOT_EXIST = 301;//该用户不存在
    public static final int WRONG_PASSWORD = 302;//密码错误

    public ErrorApi(int resultCode) {
        this(getApiExceptionMessage(resultCode));
    }

    public ErrorApi(String detailMessage) {
        super(detailMessage);
    }

    private static String getApiExceptionMessage(int code) {
        String mes = "";
        switch (code) {
            case USER_NOT_EXIST:
                mes = "账户不存在";
                break;
            case WRONG_PASSWORD:
                mes = "密码错误";
                break;
            default:
                mes = "未知错误";

        }
        return mes;
    }
}

• 现在回到前面，可以定义我们自己的APi接口啦，回到上章内容AnApiService接口文件中，这样

    /**
     * 登陆
     *
     * @param username
     * @param password
     * @return
     */
    @POST("login/loginByAccount?")
    Observable<HttpResult<LoginDataBean>> logins(@Query("username") String username, @Query("password") String password);


    /**
     * 获取销量数据
     *
     * @return
     */
    @POST("sale/getTodaySaleInfoByUserId")
    Observable<BaseHttpRequestBean<SalesDataBean>> getTodaySaleInfoByUserIds();

• 好了，现在在回到ApiServiceManger中，看看这次的请求怎么搞

 /**
     * 登录
     * @param observer
     * @param phone
     * @param password
     */
    public void logins(Subscriber<LoginDataBean> observer, String phone, String password) {
        anApiService.logins(phone, password)
                .map(new BaseHttpRequestBean<LoginDataBean>())
                .subscribeOn(Schedulers.io())//指定 subscribe() 发生在 IO 线程
                .observeOn(AndroidSchedulers.mainThread()).subscribe(observer);// 指定 Subscriber 的回调发生在主线程
    }

HttpResult()<>是用来统一出处理请求返回，将BaseHttpRequestBean<>中包含的T取出，（此处T = LoginDataBean ），最后可以根据返回做预处理，并且返回data部分

private class HttpResultFunc<T> implements Func1<BaseHttpRequestBean<T>, T> {
        @Override
        public T call(BaseHttpRequestBean<T> httpResult) {
            if (httpResult.getCode() == 301) {
                throw new ErrorApi(301);
            } else if (httpResult.getCode() == 302) {
                throw new ErrorApi(302);
            } else if (httpResult.getCode() == 200) {
                return httpResult.getData();
            } else {
                throw new ErrorApi(100);
            }
        }
    }

• 最后的就直接上代码了，是自定义的对外的接口，以及请求结果统一处理

public interface SubscriberOnNextListener<T> {
    void onNext(T t);
}

// 可自定义Dialog实现，在开始请求和结束请求时，可分别显示Dialog提醒用户
public class MySubscriber<T> extends Subscriber<T> {
    private SubscriberOnNextListener mSubscriberOnNextListener;
    private Context context;

    public MySubscriber(SubscriberOnNextListener mSubscriberOnNextListener, Context context) {
        this.mSubscriberOnNextListener = mSubscriberOnNextListener;
        this.context = context;
    }

    /**
     * 开始时调用
     */
    @Override
    public void onStart() {
        super.onStart();
        //此处可自定义显示Dialog
    }

    @Override
    public void onCompleted() {

    }

    /**
     * 错误处理
     *
     * @param e
     */
    @Override
    public void onError(Throwable e) {

    }

    /**
     * 将onNext方法中的结果返回
     *
     * @param t
     */
    @Override
    public void onNext(T t) {
        if (mSubscriberOnNextListener != null) {
            mSubscriberOnNextListener.onNext(t);
        }
    }
}

• 请求

 AnApiServiceManger.getInstance().
                logins(new MySubscriber<LoginDataBean>(new SubscriberOnNextListener<LoginDataBean>() {
                    @Override
                    public void onNext(LoginDataBean loginDataBean) {
                        Log.d(TAG, loginDataBean.getCompanyName() + "=\n=" + loginDataBean.getFullName()
                                        + "=\n=" + loginDataBean.getCompanyId() + "=\n=" + loginDataBean.getUserName());
                    }
                }), str1, edPasstext.getText().toString().trim());

好了，就这样可以简简单单的将统一处理封装起来了，请求连接就不提供了，因为是公司服务器，不属于个人不能共享。。。。。，欢迎反馈，有问题请热情告知