Test Java TLSv1.2 connection

jva-tls-test.java

import java.net.*;
import java.io.*;

class Main {
  public static void main(String[] args) throws Exception {
    
    System.setProperty("https.protocols", "TLSv1.2");
    System.setProperty("javax.net.debug", "all");    
    
    final URL url = new URL("https://your-server-to-test");
    try(final InputStream in = url.openStream()){
      //…
    }
  }
}