How to replace low res image reference at end of URL string with the higher res image reference available

From an API I'm getting a thumbnail image from the URL string similar to this format: https://website.com/05b8a817448d0e2/0_167_3000_1799/500.jpg. However, it looks very blotchy for android app development.

There is no high-res image available from the API. However, I have discovered that by changing the end of the URL, the images exist at 1000px and even 2000px.

I want to change the URL string to the higher res version that exists at the same location with the improved suffix: https://website.com/05b8a817448d0e2/0_167_3000_1799/1000.jpg

Extra requirements:

Rarely the API gives different sizes other than 500, like 1000 or 250
In rare cases it ends with .png instead of .jpg (possibly even other formats)
In rare cases the image doesn't exist at a higher res and should be left alone

So the solution needs to be quite a lot more robust that my current coding capabilities.

This is my code block in Android Studio which works fine, but doesn't cover the extra requirements. I have only been coding in Java and Android Studio a few months so there may be some issues with it:

 /**
 * Load an image from a URL and return a {@link Bitmap}
 *
 * @param url string of the URL link to the image
 * @return Bitmap of the image
 */
private static Bitmap downloadBitmap(String url) {
    Bitmap bitmap = null;
    String newUrlString = url;

    try {
        // Change 500px image to 1000px image
        URL oldUrl = new URL(url);
        if (url.endsWith("500.jpg")) {
            newUrlString = oldUrl.toString().replaceFirst("500.jpg", "1000.jpg");
        }

        InputStream inputStream = new URL(newUrlString).openStream();
        bitmap = BitmapFactory.decodeStream(inputStream);
    } catch (Exception e) {
        Log.e(LOG_TAG, e.getMessage());
    }
    return bitmap;
}

Solution

try the following:

protected class ImageLoader extends AsyncTask<String, Void, Bitmap> {
        protected Bitmap doInBackground(String... urls) {
            Bitmap bitmap = null;
            String originalUrl = urls[0];
            String url = urls[0].replaceFirst("/500.", "/1000.");
            try {
                InputStream inputStream = new URL(url).openStream();
                bitmap = BitmapFactory.decodeStream(inputStream);
            } catch (Exception e) {
                try {
                    InputStream inputStream = new URL(originalUrl).openStream();
                    bitmap = BitmapFactory.decodeStream(inputStream);
                } catch (Exception ignored) {
                }
            }
            return bitmap;
        }

        protected void onPostExecute(Bitmap bitmap) {
            //do whatever you want with the result.
            if(bitmap!=null)
            image.setImageBitmap(bitmap);
        }
    }

What I did here, is that I created an AsyncTask (since your original code will throw NetworkOnMainThreadException ) called ImageLoader. It will handle requesting the image url; if it fails to get the 1000px version, it will failover to the 500px version of the image. Hope this helps.