@java.lang.Override
  public final boolean isInitialized() {
    byte isInitialized = memoizedIsInitialized;
    if (isInitialized == 1) return true;
    if (isInitialized == 0) return false;

    memoizedIsInitialized = 1;
    return true;
  }
<pre>
Google Cloud Storage image location, or publicly-accessible image
URL. If both `content` and `source` are provided for an image, `content`
takes precedence and is used to perform the image annotation request.
</pre>

<code>.google.cloud.vision.v1p4beta1.ImageSource source = 2;</code>
java-vision/proto-google-cloud-vision-v1p4beta1/src/main/java/com/google/cloud/vision/v1p4beta1/Image.java