json array -rest api wordpress for android

jsonarray

package com.example.aladin_bureau.wordpress_wp;

import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ListView;

import com.squareup.okhttp.OkHttpClient;
import com.squareup.okhttp.Request;
import com.squareup.okhttp.Response;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import adapters.postadapter;
import entities.*;
public class MainActivity extends AppCompatActivity implements onFeedListener {
ListView list ;
    ArrayList<posts>postses;
    postadapter adapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        list=(ListView)findViewById(R.id.list1);
        adapter= new postadapter(getApplicationContext(),postses);
        list.setAdapter(adapter);
        FeedTask task = new FeedTask(this);
        task.execute("https://blog.rumi-app.org/wp-json/wp/v2/posts");

    }

    @Override
    public void onFeed(JSONArray array) {
        int length = array.length();
        postses=new ArrayList<>();

        for (int i=0 ; i< length;i++){
            JSONObject object = array.optJSONObject(i);
            posts post = new posts();
            post.setDescription(object.optString("title"));
            post.setDescription(object.optString("excerpt"));
            post.setDescription("");
            postses.add(post);
        }
        adapter.addAll(postses);
        adapter.notifyDataSetChanged();


    }




    public class  FeedTask extends AsyncTask<String,Void,JSONArray>{
          private onFeedListener listener ;

        public FeedTask (onFeedListener listener){
            this.listener=listener;
        }
        @Override
        protected JSONArray doInBackground(String... params) {

            String url = params[0];
            OkHttpClient client = new OkHttpClient();
            Request.Builder builder = new Request.Builder();
            Request request=builder.url(url).build();
            try {
                Response response = client.newCall(request).execute();
                String json = response.body().string();
                JSONObject object = new JSONObject();
                JSONArray array = object.optJSONArray("posts");
                return array;
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(JSONArray array) {

            super.onPostExecute(array);
            if (null==array){
                return;
            } else if(null!=listener){
                listener.onFeed(array);
            }
        }
    }

}