I have created a snapshot for a grafana dashboard. When I embed the url in iframe in external app it works well. Bit if I try to hit the url in Java client and pass the HTML to Js to load in front end , only alert is getting displayed. Can you please explain why is that.can I get the HTML content from Java side and pass it to front end so that url embedded will be hidden
No, you cannot. Grafana is a complex application with backend and frontend components.
However, you can share a panel as a png image, see documentation. Maybe this will help you.