Refer to the following Hypertext Markup Language (HTML) form in Figure 1 below:

Write a Java Servlet to handle the above Figure 1 update request from client assuming that the application has a database with a table named staff. The Java Servlet will execute the update of the telephone number based on the given staff ID and list out all the staff names, staff ID and telephone numbers if the update is successful. You may provide any suitable names to represent the needed attributes from the table staff. Provide all the necessary database connection statements with disregard to the type of database management system used, the database driver and the name of the database.