@Bean 
  EmbeddedServletContainerCustomizer containerCustomizer(
        @Value("${keystore.file}") Resource keystoreFile,
        @Value("${keystore.pass}") String keystorePass) throws Exception {

      String absoluteKeystoreFile = keystoreFile.getFile().getAbsolutePath();
      
      return (ConfigurableEmbeddedServletContainer container) -> {

          if (container instanceof TomcatEmbeddedServletContainerFactory) {

              TomcatEmbeddedServletContainerFactory tomcat = (TomcatEmbeddedServletContainerFactory) container;
              tomcat.addConnectorCustomizers(
                      (connector) -> {
                          connector.setPort(8443);
                          connector.setSecure(true);
                          connector.setScheme("https");
                          Http11NioProtocol proto = (Http11NioProtocol) connector.getProtocolHandler();
                          proto.setSSLEnabled(true);
                          proto.setKeystoreFile(absoluteKeystoreFile);
                          proto.setKeystorePass(keystorePass);
                          proto.setKeystoreType("PKCS12");
                          proto.setKeyAlias("tomcat");
                      }
              );
          }
      };
  }