checks google play for newer version using Jsoup and rxandroid

RxVersionChecker.java

package m7mdra.io.services.util;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.net.Uri;

import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.select.Elements;

import java.util.concurrent.Callable;

import io.reactivex.Observable;
import io.reactivex.android.schedulers.AndroidSchedulers;
import io.reactivex.functions.Consumer;
import io.reactivex.schedulers.Schedulers;
import m7mdra.io.services.BuildConfig;
import m7mdra.io.services.R;


public class VersionChecker {
    private static String CURRENT_VERSION= BuildConfig.VERSION_NAME;
    private Activity activity;
    private final String appPackageName;

    public VersionChecker(Activity activity){
        this.activity=activity;
        appPackageName = activity.getPackageName();
    }
    public void check(){
        Observable.fromCallable(new Callable<Elements>() {
            @Override
            public Elements call() throws Exception {
                Document doc = Jsoup.connect("https://play.google.com/store/apps/details?id="+appPackageName).get();
                return doc.getElementsByAttributeValue("itemprop","softwareVersion");
            }
        }).subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(new Consumer<Elements>() {
                    @Override
                    public void accept(Elements s) throws Exception {
                        PLogger.p(s.text());
                        if (!s.text().equals(CURRENT_VERSION))
                            if (!activity.isFinishing()) //to avoid crashing when activiy is not visible
                            showUpdate().setMessage("Show message here").create().show();
                    }
                });
    }
    private AlertDialog.Builder showUpdate(){
        return new AlertDialog.Builder(activity)
                .setTitle("title here")
                .setCancelable(false)
                .setPositiveButton(activity.getString(R.string.ok), new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        try {
                           activity.startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("market://details?id=" + appPackageName)));
                        }catch (android.content.ActivityNotFoundException ignored) {
                            activity.startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("http://play.google.com/store/apps/details?id=" + appPackageName)));
                            ignored.printStackTrace();
                        }

                    }
                });

    }
}

VersionChecker.java

package m7mdra.io.services.util;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.net.Uri;

import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.select.Elements;

import java.io.IOException;

import m7mdra.io.services.BuildConfig;
import m7mdra.io.services.R;



public class VersionChecker implements Runnable  {
    private final String CURRENT_VERSION= BuildConfig.VERSION_NAME;
    private Activity activity;
    private final String appPackageName;

    public VersionChecker(Activity activity){
        this.activity=activity;
        appPackageName = activity.getPackageName();
    }


    private AlertDialog.Builder showUpdate(){
        return new AlertDialog.Builder(activity)
                .setTitle("title here")
                .setCancelable(false)
                .setPositiveButton(activity.getString(R.string.ok), new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {

                        try {
                           activity.startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("market://details?id=" + appPackageName)));
                        }catch (android.content.ActivityNotFoundException ignored) {
                            activity.startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("http://play.google.com/store/apps/details?id=" + appPackageName)));
                            ignored.printStackTrace();
                        }
                    }
                });

    }

    @Override
    public void run() {
        try {
            Document doc = Jsoup.connect("https://play.google.com/store/apps/details?id="+appPackageName).get();
            Elements s = doc.getElementsByAttributeValue("itemprop","softwareVersion");
            PLogger.p(s.text());
            if (!s.text().equals(CURRENT_VERSION))
                if (!activity.isFinishing())
                    activity.runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            showUpdate().setMessage("message here").create().show();
                        }
                    });
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}