Android JsonArrayRequest

package com.example.restapi_test;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;

import com.android.volley.AuthFailureError;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.JsonArrayRequest;
import com.android.volley.toolbox.JsonObjectRequest;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;

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

import java.util.HashMap;
import java.util.Map;


public class MainActivity extends AppCompatActivity {
    private String serverURL = "http://bigdata.hamcho.net/restapi/";
    RequestQueue requestQueue;
    Gson gson;

    TextView tv;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        tv = findViewById(R.id.tv);


        tv.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                requestLotto();
            }
        });
        gson = new GsonBuilder().create();
        if(requestQueue == null){
            requestQueue = Volley.newRequestQueue(getApplicationContext());
        }

    }

    public void requestLotto(){

        JsonArrayRequest request = new JsonArrayRequest(Request.Method.GET, serverURL + "chamber/", null, new Response.Listener<JSONArray>() {
            @Override
            public void onResponse(JSONArray response) {
            tv.setText(response.toString());
            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {

            }
        });


        request.setShouldCache(false);
        requestQueue.add(request);
    }




}