Okhttp二次封装

//首先我们先写一个接口

public interface IHttp {
//    GET请求
    <T>void get(String url, Map<String,String>paramsMap,MyCallBack<T>callBack);
//    POST请求
    <T>void post(String url,Map<String,String>paramsMap,MyCallBack<T>callBack);

}      

//MyCallBack接口

public interface MyCallBack<T> {
//    请求成功的方法
    void success(T t);
//    请求失败的方法
    void faile(String msg);
}      

//单例

/*
* 将HttpUtils实例通过单例提供出去
* */
public class HttpUtils implements IHttp {
    //    创建私有的静态的本类对象
    private static HttpUtils utils;
    //    创建私有的OkhttpClient对象
    private OkHttpClient client;

    private HttpUtils() {
        client = new OkHttpClient();
    }

    public static synchronized IHttp getInstance() {
        if (utils == null) {
            utils = new HttpUtils();
        }
        return utils;
    }

    //http://www.baidu.com?name=zhangsan&pwd=123
    @Override
    public <T> void get(String baseUrl, Map<String, String> paramsMap, final MyCallBack<T> callBack) {
        StringBuffer buffer = new StringBuffer();
        buffer.append("?");
        if (paramsMap != null && paramsMap.size() > 0) {
            for (String key : paramsMap.keySet()) {
                String value = paramsMap.get(key);
                buffer.append(key).append("=").append(value).append("&");
            }
            buffer.toString().trim().substring(0, buffer.toString().trim().length() - 1);
        }
        String getUrl = buffer.toString().trim();
        Request build = new Request.Builder().url(getUrl).build();
        client.newCall(build).enqueue(new Callback() {
            @Override
            public void onFailure(Call call, IOException e) {
                callBack.faile(e.getMessage());
            }

            @Override
            public void onResponse(Call call, Response response) throws IOException {
                String json = response.body().string();
                callBack.success(getParseData(json, callBack));

            }
        });
    }

    /**
     * 通过反射的形式,将CallBack接口的实现类的类类型
     * 然后将类类型传到Gson中，最后得到解析后的结果(类类型对应的实体)
     *
     * @param jsonData
     * @param callBack
     * @param <T>
     * @return
     */
    private <T> T getParseData(String jsonData, MyCallBack<T> callBack) {
        Type[] interfacetypes = callBack.getClass().getGenericInterfaces();
        Type[] types = ((ParameterizedType) interfacetypes[0]).getActualTypeArguments();
        Type type = types[0];
        Gson gson = new Gson();
        T t = gson.fromJson(jsonData, type);
        return t;
    }

    //http://www.baidu.com
    @Override
    public <T> void post(String url, Map<String, String> paramsMap, final MyCallBack<T> callBack) {
        FormBody.Builder formBuilder = new FormBody.Builder();
        for (String key : paramsMap.keySet()) {
            formBuilder.add(key, paramsMap.get(key));
        }
        FormBody body = formBuilder.build();
        Request build = new Request.Builder().url(url).post(body).build();
        client.newCall(build).enqueue(new Callback() {
            @Override
            public void onFailure(Call call, IOException e) {
                callBack.faile(e.getMessage());
            }

            @Override
            public void onResponse(Call call, Response response) throws IOException {
                String json = response.body().string();
                callBack.success(getParseData(json, callBack));
            }
        });
    }
}