E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #1 ERROR for Android

Issue

My Code is below. It is giving an error in Android Studio. Anyone please help me. My PHP code is OK but why is it giving this error?

Register.java

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;

public class Register extends AppCompatActivity {
    EditText et_name, et_number;


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

        et_name = (EditText) findViewById(R.id.nametxt);
        et_number = (EditText) findViewById(R.id.numbertxt);

    }

    public void userReg(View view){

        String names = et_name.getText().toString();
        String numbers = et_number.getText().toString();

        String method = "register";
        BackgroundTask backgroundTask = new BackgroundTask(this);
        backgroundTask.execute(method,names,numbers);
        finish();


    }
}

And My Background.java Code is

import android.content.Context;
import android.net.Uri;
import android.os.AsyncTask;
import android.widget.Toast;

import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLEncoder;

import javax.net.ssl.HttpsURLConnection;

public class BackgroundTask extends AsyncTask<String,Void,String> {

    Context ctx;

    BackgroundTask(Context ctx){

        this.ctx = ctx;

    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
    }

    @Override
    protected String doInBackground(String... params) {
        String reg_url = "http://192.168.1.2/logins/register.php";
        String method = params[0];
        if(method.equals("register")){

            String name = params[1];
            String number = params[2];
            try {
                URL url = new URL(reg_url);
                HttpsURLConnection httpsURLConnection = (HttpsURLConnection) url.openConnection();
                httpsURLConnection.setRequestMethod("POST");
                httpsURLConnection.setDoOutput(true);
                OutputStream os = httpsURLConnection.getOutputStream();
                BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(os,"UTF-8"));
                String data = URLEncoder.encode("names","UTF-8")+"="+URLEncoder.encode(name,"UTF-8")+"&"
                        +URLEncoder.encode("numbers","UTF-8")+"="+URLEncoder.encode(number,"UTF-8");
                bufferedWriter.write(data);
                bufferedWriter.flush();
                bufferedWriter.close();
                os.close();
                InputStream IS = httpsURLConnection.getInputStream();
                IS.close();
                return "Registration Success...";
            } catch (MalformedURLException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }


        }

        return null;
    }

    @Override
    protected void onProgressUpdate(Void... values) {
        super.onProgressUpdate(values);
    }

    @Override
    protected void onPostExecute(String result) {
        Toast.makeText(ctx,result,Toast.LENGTH_LONG).show();
    }
}

And my Androidmainfest.xml is

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

Android Studio Error is :

E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #1 Process: com.example.smtanverhossain.myphpmysqlapplication, PID: 5445 java.lang.RuntimeException: An error occured while executing doInBackground() at android.os.AsyncTask$3.done(AsyncTask.java:300) at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355) at java.util.concurrent.FutureTask.setException(FutureTask.java:222) at java.util.concurrent.FutureTask.run(FutureTask.java:242) at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587) at java.lang.Thread.run(Thread.java:818) Caused by: java.lang.ClassCastException: com.android.okhttp.internal.http.HttpURLConnectionImpl cannot be cast to javax.net.ssl.HttpsURLConnection at com.example.smtanverhossain.myphpmysqlapplication.BackgroundTask.doInBackground(BackgroundTask.java:46) at com.example.smtanverhossain.myphpmysqlapplication.BackgroundTask.doInBackground(BackgroundTask.java:19) at android.os.AsyncTask$2.call(AsyncTask.java:288) at java.util.concurrent.FutureTask.run(FutureTask.java:237) at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)  at java.lang.Thread.run(Thread.java:818)

Solution

The error is explained in the log: Caused by: java.lang.ClassCastException: com.android.okhttp.internal.http.HttpURLConnectionImpl cannot be cast to javax.net.ssl.HttpsURLConnection

This means you can't cast to HttpsURLConnection at this line:

HttpsURLConnection httpsURLConnection = (HttpsURLConnection) url.openConnection();

The reason for this is because your URL uses HTTP instead of HTTPS. When you call url.openConnection() with HTTP, it returns a HttpURLConnection and same applies for HTTPS. This is stated in the documentation.

The solution should be to replace all HttpsURLConnection with HttpURLConnection and remove the cast to HttpsURLConnection.

Answered By - Tohu