get high res picture from social profiles

profile.java

    /**
     * used for fb  AuthService provides Observables with gives the profile pic,
     * this function uses that observable to display the profile pic
     * @param profilePicObservable Observable that provides url for high res profile pic
     */
    private void displayPic(Observable<String> profilePicObservable) {
        profilePicObservable
                .observeOn(AndroidSchedulers.mainThread())
                .subscribeOn(Schedulers.io())
                .subscribe(
                        url -> {
                            //saveProfilePicture(url);
                            profileView.displayProfilePic(url);
                        },
                        Throwable::printStackTrace
                );

    }

    /**
     * the profile pic url in case of twitter is sth like
     * http://pbs.twimg.com/profile_images/463646119960920064/_lMH5iFt_normal.jpeg
     *
     * Omit the underscore and variant to retrieve the original image.
     * NOTE THE IMAGE CAN BE VERY LARGE
     * todo use cloudinary stuff instead
     *
     * @param lowResUrl the default low res image
     * @return highResUrl
     */
    private String parseTwitterUrl(String lowResUrl) {
        return lowResUrl.replace("_normal", "");
    }

    /**
     *  google returns the profile url as
     *  https://lh5.googleusercontent.com/-GoXxObG2mVE/AAAAAAAAAAI/AAAAAAAABFY/PzVrrZdkQYQ/s96-c/photo.jpg
     *  here 96 is the width and height, to get a full res we can put our required dimensions
     *  and request
     *  todo use cloudinary stuff instead
     *
     *  @param lowResUrl The default low res url
     */
    private String parseGoogleUrl(String lowResUrl) {
        // find the dimension and change it to 400dp
        String[] urlParts = lowResUrl.split("/");
        String dimPart = urlParts[urlParts.length - 2];
        String[] dimValue = dimPart.split("-");
        dimValue[0] = "s400";

        // recreate the url
        urlParts[urlParts.length - 2] = TextUtils.join("-", dimValue);
        return TextUtils.join("/", urlParts);
    }