dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'androidx.appcompat:appcompat:1.1.0'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    implementation 'com.google.android.material:material:1.0.0'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test.ext:junit:1.1.1'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'

    //dependency for recaptcha (safetynet)
    implementation 'com.google.android.gms:play-services-safetynet:17.0.0'

    //dependency for fast networking for networking
    implementation 'com.android.volley:volley:1.1.0'
}

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

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

import androidx.appcompat.app.AppCompatActivity;
import androidx.annotation.NonNull;

//volley
import com.android.volley.DefaultRetryPolicy;
import com.android.volley.RequestQueue;
import com.android.volley.Request;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;


import com.google.android.gms.common.api.ApiException;
import com.google.android.gms.common.api.CommonStatusCodes;
import com.google.android.gms.safetynet.SafetyNet;
import com.google.android.gms.safetynet.SafetyNetApi;
import com.google.android.gms.tasks.OnFailureListener;
import com.google.android.gms.tasks.OnSuccessListener;

import org.json.JSONObject;

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

import android.view.Menu;
import android.view.MenuItem;

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        btn = findViewById(R.id.reCaptcha);
        txtV = findViewById(R.id.verifyText);
        btn.setOnClickListener(this);

        requestQueue = Volley.newRequestQueue(getApplicationContext());
    }

    public void onClick(View view){
        SafetyNet.getClient(this).verifyWithRecaptcha(Site_Key)
                .addOnSuccessListener(this, new OnSuccessListener <SafetyNetApi.RecaptchaTokenResponse>(){
                    @Override
                    public void onSuccess(SafetyNetApi.RecaptchaTokenResponse response){
                        if (!response.getTokenResult().isEmpty()){
                            handleCaptchaResult(response.getTokenResult());

                        }
                    }
        })
                .addOnFailureListener(this, new OnFailureListener() {
                    @Override
                    public void onFailure(@NonNull Exception e) {
                        if (e instanceof  ApiException){
                            ApiException apiException = (ApiException)e;
                            Log.d(TAG, "Error Message: " + CommonStatusCodes.getStatusCodeString(apiException.getStatusCode()));
                        } else {
                            Log.d(TAG, "Unknown error type or error" + e.getMessage());
                        }
                    }
                });
    }

void handleCaptchaResult(final String responseToken){
        String url = "https://www.google.com/recaptcha/api/siteverify"; //consider using global variable here
        StringRequest request = new StringRequest(Request.Method.POST, url, new Response.Listener<String>() {
            @Override
            public void onResponse(String response) {
                try {
                    JSONObject jsonObject = new JSONObject(response);
                    if (jsonObject.getBoolean("success")) {
                        txtV.setTextSize(35);
                        txtV.setText("Congratulations! You're not a robot anymore");
                    }
                } catch (Exception ex) {
                    Log.d(TAG, "Error message: " + ex.getMessage());
                }
            }
        },
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        Log.d(TAG, "Error message: " + error.getMessage());
                    }
                })
        {
            @Override
            protected Map<String,String> getParams(){
                Map<String,String> params = new HashMap<>();
                params.put("secret", Site_Secret_Key);
                params.put("response", responseToken);
                return params;
            }
        };
        request.setRetryPolicy(new DefaultRetryPolicy(50000,DefaultRetryPolicy.DEFAULT_MAX_RETRIES,DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));
        requestQueue.add(request);
    }

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

import androidx.appcompat.app.AppCompatActivity;
import androidx.annotation.NonNull;

//volley
import com.android.volley.DefaultRetryPolicy;
import com.android.volley.RequestQueue;
import com.android.volley.Request;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;


import com.google.android.gms.common.api.ApiException;
import com.google.android.gms.common.api.CommonStatusCodes;
import com.google.android.gms.safetynet.SafetyNet;
import com.google.android.gms.safetynet.SafetyNetApi;
import com.google.android.gms.tasks.OnFailureListener;
import com.google.android.gms.tasks.OnSuccessListener;

import org.json.JSONObject;

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

import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.android.material.snackbar.Snackbar;

import androidx.appcompat.widget.Toolbar;


import android.view.Menu;
import android.view.MenuItem;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    String TAG = MainActivity.class.getSimpleName();
    Button btn;
    TextView txtV;
 // TODO - replace the SITE KEY with yours
    String Site_Key = "6LcFP8cUAAAAALPrBpvuSPileb7vd"; //consider making global variable(this will not work not a valid key)
 // TODO - replace the Secret KEY with yours
    String Site_Secret_Key = "6LcFP8cUAAAAAJyKpv8FKRkd1bSnR-"; //consider making global variable(this will not work not a valid key)
    RequestQueue requestQueue;

    //application space controls
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        btn = findViewById(R.id.reCaptcha);
        txtV = findViewById(R.id.verifyText);
        btn.setOnClickListener(this);

        requestQueue = Volley.newRequestQueue(getApplicationContext());
    }

    @Override
    public void onClick(View view){
        SafetyNet.getClient(this).verifyWithRecaptcha(Site_Key)
                .addOnSuccessListener(this, new OnSuccessListener <SafetyNetApi.RecaptchaTokenResponse>(){
                    @Override
                    public void onSuccess(SafetyNetApi.RecaptchaTokenResponse response){
                        if (!response.getTokenResult().isEmpty()){
                            handleCaptchaResult(response.getTokenResult());

                        }
                    }
        })
                .addOnFailureListener(this, new OnFailureListener() {
                    @Override
                    public void onFailure(@NonNull Exception e) {
                        if (e instanceof  ApiException){
                            ApiException apiException = (ApiException)e;
                            Log.d(TAG, "Error Message: " + CommonStatusCodes.getStatusCodeString(apiException.getStatusCode()));
                        } else {
                            Log.d(TAG, "Unknown error type or error" + e.getMessage());
                        }
                    }
                });
    }

    void handleCaptchaResult(final String responseToken){
        String url = "https://www.google.com/recaptcha/api/siteverify"; //consider using global variable here
        StringRequest request = new StringRequest(Request.Method.POST, url, new Response.Listener<String>() {
            @Override
            public void onResponse(String response) {
                try {
                    JSONObject jsonObject = new JSONObject(response);
                    if (jsonObject.getBoolean("success")) {
                        txtV.setTextSize(35);
                        txtV.setText("Congratulations! You're not a robot anymore");
                    }
                } catch (Exception ex) {
                    Log.d(TAG, "Error message: " + ex.getMessage());
                }
            }
        },
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        Log.d(TAG, "Error message: " + error.getMessage());
                    }
                })
        {
            @Override
            protected Map<String,String> getParams(){
                Map<String,String> params = new HashMap<>();
                params.put("secret", Site_Secret_Key);
                params.put("response", responseToken);
                return params;
            }
        };
        request.setRetryPolicy(new DefaultRetryPolicy(50000,DefaultRetryPolicy.DEFAULT_MAX_RETRIES,DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));
        requestQueue.add(request);
    }
}

<androidx.constraintlayout.widget.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">
    <LinearLayout
        android:layout_height="match_parent"
        android:layout_width="match_parent"
        android:orientation="vertical">

        <Button
            android:id="@+id/reCaptcha"
            android:layout_height="wrap_content"
            android:layout_width="wrap_content"
            android:text="Show reCAPTCHA"/>

        <TextView
            android:id="@+id/verifyText"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:capitalize="characters"
            android:text="Hello World"
            android:textSize="24sp" />

    </LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>