0. Install Tomcat 8.5.30 (Remember install JDK 8 first.) and Nginx 1.10.3

# cd ~/
# wget http://ftp.mirror.tw/pub/apache/tomcat/tomcat-8/v8.5.30/bin/apache-tomcat-8.5.30.tar.gz
# tar zxvf apache-tomcat-8.5.30.tar.gz
# ./apache-tomcat-8.5.30/bin/catalina.sh start
# sudo apt-get update
# sudo apt-get install nginx

1. Create self-sign ssl

# sudo mkdir /etc/nginx/ssl
# sudo openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /etc/nginx/ssl/XXXXX.key -out /etc/nginx/ssl/XXXXX.crt
# sudo openssl dhparam -out /etc/nginx/ssl/dhparam.pem 4096 <--- You can use 2048 length.

2. Modified nginx configuration file

# sudo vim /etc/nginx/sites-available/default
...
...
...
server {
        listen 80 default_server;
        listen [::]:80 default_server;

        server_name 192.168.1.1;  <--- You can change to domain name

        return 301 https://192.168.1.1$request_uri; <--- You can change to domain name
}
...
...
...
server {
        # SSL configuration
        #
        listen 443 ssl http2 default_server;
        listen [::]:443 ssl http2 default_server;

        ssl_certificate /etc/nginx/ssl/XXXXX.crt;
        ssl_certificate_key /etc/nginx/ssl/XXXXX.key;
        ssl_dhparam /etc/nginx/ssl/dhparam.pem;

        server_name 192.168.1.1;  <--- You can change to domain name

        # Specify a charset
        charset utf-8;

        # disable autoindex
        autoindex off;

        location / {
                # First attempt to serve request as file, then
                # as directory, then fall back to displaying a 404.
                proxy_pass http://127.0.0.1:8080;  <-------  Tomcat Service
                #try_files $uri $uri/ =404;
        }
        ...
        ...
        ...
}
...
...
...

3. Restart Nginx

# sudo nginx -t
# sudo systemctl restart nginx

https://www.digitalocean.com/community/tutorials/how-to-create-an-ssl-certificate-on-nginx-for-ubuntu-14-04
https://blog.gtwang.org/linux/nginx-create-and-install-ssl-certificate-on-ubuntu-linux/