What version of TLS are we on?

How to check TLS version HTTPS?

I have a web application in AWS which has an API exposed through HTTPS.

This API works fine when the client has an SSL certificate but fails with "An error occurred during a connection to xxx.xxx:443" when the client does not have an SSL certificate. The exception thrown is "Error occurred during WebSocket handshake: Unexpected response code: 1011".

I am using Java and the Apache HTTP client version 4. I am able to connect to the API with a client with an SSL certificate, but the same client with no SSL certificate throws the exception I mentioned. How can I find out the version of TLS that is being used in the HTTPS connection? You can use the following code: HttpURLConnection con = (HttpURLConnection) new URL("").openConnection(); int responseCode = con.getResponseCode(); System.println(con.getResponseMessage());
Con.disconnect(); System.println(con.getResponseMessage());
If the response code is 4xx then it's HTTP level error, if the response code is 5xx then it's server side error.