ok封装和解析json封装

OkHttp3Utils 

import android.os.Environment;
import android.os.Handler;

import java.io.File;
import java.util.concurrent.TimeUnit;

import okhttp3.Cache;
import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.OkHttpClient;
import okhttp3.Request;



public class OkHttp3Utils {
    /**
     * 懒汉 安全 加同步
     * 私有的静态成员变量 只声明不创建
     * 私有的构造方法
     * 提供返回实例的静态方法
     */
    private static OkHttp3Utils okHttp3Utils = null;

    private OkHttp3Utils() {
    }

    public static OkHttp3Utils getInstance() {
        if (okHttp3Utils == null) {
            //加同步安全
            synchronized (OkHttp3Utils.class) {
                if (okHttp3Utils == null) {
                    okHttp3Utils = new OkHttp3Utils();
                }
            }

        }

        return okHttp3Utils;
    }

    private static OkHttpClient okHttpClient = null;

    public synchronized static OkHttpClient getOkHttpClient() {
        if (okHttpClient == null) {
            File sdcache = new File(Environment.getExternalStorageDirectory(), "cache");
            int cacheSize = 10 * 1024 * 1024;
            //拦截器

            okHttpClient = new OkHttpClient.Builder().connectTimeout(15, TimeUnit.SECONDS)
                    //添加OkHttp3的拦截器
                    .writeTimeout(20, TimeUnit.SECONDS).readTimeout(20, TimeUnit.SECONDS)
                    .cache(new Cache(sdcache.getAbsoluteFile(), cacheSize))
                    .build();
        }
        return okHttpClient;
    }

    private static Handler mHandler = null;

    public synchronized static Handler getHandler() {
        if (mHandler == null) {
            mHandler = new Handler();
        }

        return mHandler;
    }

    /**
     * get请求
     * 参数1 url
     * 参数2 回调Callback
     */

    public static void doGet(String url, Callback callback) {

        //创建OkHttpClient请求对象
        OkHttpClient okHttpClient = getOkHttpClient();
        //创建Request
        Request request = new Request.Builder().url(url).build();
        //得到Call对象
        Call call = okHttpClient.newCall(request);
        //执行异步请求
        call.enqueue(callback);


    }


}

GsonObjectCallback

import android.os.Handler;

import com.google.gson.Gson;

import java.io.IOException;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;

import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.Response;

/**
 * 1. 类的用途 如果要将得到的json直接转化为集合 建议使用该类
 * 该类的onUi() onFailed()方法运行在主线程
 *  
 */

public abstract class GsonObjectCallback<T> implements Callback {
    private Handler handler = OkHttp3Utils.getInstance().getHandler();

    //主线程处理
    public abstract void onUi(T t);

    //主线程处理
    public abstract void onFailed(Call call, IOException e);

    //请求失败
    @Override
    public void onFailure(final Call call, final IOException e) {
        handler.post(new Runnable() {
            @Override
            public void run() {
                onFailed(call, e);
            }
        });
    }

    //请求json 并直接返回泛型的对象 主线程处理
    @Override
    public void onResponse(Call call, Response response) throws IOException {
        //如果返回的数据超过1M就不要使用string方法，这样会把数据全部加载到内存中，应该使用流；
        String json = response.body().string();
        Class<T> cls = null;

        Class clz = this.getClass();
        ParameterizedType type = (ParameterizedType) clz.getGenericSuperclass();
        Type[] types = type.getActualTypeArguments();
        cls = (Class<T>) types[0];
        Gson gson = new Gson();
        final T t = gson.fromJson(json, cls);
        handler.post(new Runnable() {
            @Override
            public void run() {
                onUi(t);
            }
        });
    }
}


//使用

private void getData() {
    OkHttp3Utils.doGet("http://news-at.zhihu.com/api/4/theme/11", new GsonObjectCallback() {
        @Override
        public void onUi(NewsBean userBean) {
            Toast.makeText(MainActivity.this, userBean.getName(), Toast.LENGTH_SHORT).show();
            Toast.makeText(MainActivity.this, userBean.getImage(), Toast.LENGTH_SHORT).show();
        }

        @Override
        public void onFailed(Call call, IOException e) {
        }
    });
}

GsonArrayCallback

import android.os.Handler;

import com.google.gson.Gson;
import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
import com.google.gson.JsonParser;

import java.io.IOException;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.List;

import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.Response;

/**
 * 1. 类的用途 如果要将得到的json直接转化为集合 建议使用该类
 * 该类的onUi() onFailed()方法运行在主线程
 * 2. @author forever
 * 3. @date 2017/9/24 18:47
 */

public abstract class GsonArrayCallback<T> implements Callback {
    private Handler handler = OkHttp3Utils.getInstance().getHandler();

    //主线程处理
    public abstract void onUi(List<T> list);

    //主线程处理
    public abstract void onFailed(Call call, IOException e);

    //请求失败
    @Override
    public void onFailure(final Call call, final IOException e) {
        handler.post(new Runnable() {
            @Override
            public void run() {
                onFailed(call, e);
            }
        });
    }

    //请求json 并直接返回集合 主线程处理
    @Override
    public void onResponse(Call call, Response response) throws IOException {
        final List<T> mList = new ArrayList<T>();

        String json = response.body().string();
        JsonArray array = new JsonParser().parse(json).getAsJsonArray();

        Gson gson = new Gson();

        Class<T> cls = null;
        Class clz = this.getClass();
        ParameterizedType type = (ParameterizedType) clz.getGenericSuperclass();
        Type[] types = type.getActualTypeArguments();
        cls = (Class<T>) types[0];

        for(final JsonElement elem : array){
            //循环遍历把对象添加到集合
            mList.add((T) gson.fromJson(elem, cls));
        }

        handler.post(new Runnable() {
            @Override
            public void run() {
                onUi(mList);

            }
        });


    }
}