AndroidManifest.xml:

<uses-permission android:name="android.permission.INTERNET" />

main.xml:

 <?xml version="1.0" encoding="utf-8"?>
    <LinearLayout
      xmlns:android="http://schemas.android.com/apk/res/android"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:gravity="center"
      android:orientation="vertical">

      <TextView
        android:id="@+id/tv"
        android:text="@string/hello_world"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"/>

    </LinearLayout>

RequestJson.java:

import android.os.AsyncTask;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import android.widget.TextView;
import org.json.JSONObject;
import org.json.JSONException;


public class RequestJson extends AsyncTask {
    private final String apiUrl,param;
    private final TextView textView;


    public RequestJson(String apiUrl, String param, TextView textView) {
        this.apiUrl = apiUrl;
        this.param = param;
        this.textView = textView;
    }

    @Override
    protected String doInBackground(Void... voids) {
        try {
            URL url = new URL(apiUrl);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setRequestMethod("GET");
            conn.setRequestProperty("Accept", "application/json");

            if (conn.getResponseCode() != 200) {
                throw new RuntimeException("Failed : HTTP error code : " + conn.getResponseCode());
            }

            BufferedReader br = new BufferedReader(new InputStreamReader((conn.getInputStream())));

            String output;
            StringBuilder responseBuilder = new StringBuilder();
            while ((output = br.readLine()) != null) {
                responseBuilder.append(output);
            }

            conn.disconnect();

            return responseBuilder.toString();

        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    public String getKeyFromJson(String jsonResponse) {
        try {
            JSONObject jsonObject = new JSONObject(jsonResponse);
            String key = jsonObject.getString(param);
            return key;
        } catch (JSONException e) {
            e.printStackTrace();
            return null;
        }
    }

	@Override
    protected void onPostExecute(String jsonResponse) {
        super.onPostExecute(jsonResponse);
        if (jsonResponse != null) {
            String key = getKeyFromJson(jsonResponse);
            if (key != null) {
                textView.setText(key);
            }
        }
    }
}

MainActivity.java:

import android.os.Bundle;
import android.widget.TextView;
import android.app.Activity;


public class MainActivity extends Activity {
    private TextView textView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        textView = findViewById(R.id.tv);

        String url = "https://api.coder-guru.com/v1/calendar/PeW725u71ed9853f97d5d1LOieca3f7/1985-01-07";
		RequestJson apiExample = new RequestJson(url,"mm_date_str",textView);
		apiExample.execute();
		
    }
	
}

Output:

  
၁၃၄၆ ခုနှစ်၊ ပြာသို လပြည့်ကျော် ၂ ရက်၊ တနင်္လာနေ့။