JavaFX WebEngine等待ajax完成

I'm developing a data mining application in JavaFX which relies on the WebView (and thus also the WebEngine). The mining happens in 2 steps: first the user uses the UI to navigate to a website in the WebView to configure where interesting data can be searched. Second, using a background task that periodically runs, a WebEngine loads the same document and tries to extract the data from the loaded document.I'm developing a data mining application in Jav