You may set the Japan Calendar as widget. There are also widgets for Christmas and New Year count down. Events Calendar.
You can select three, four and five-day long weekend option on the form and generate calendar as suitable for you. Japan Public Holidays 2021 This page contains a national calendar of all 2021 public holidays. These dates may be modified as official changes are announced, so please check back regularly for updates. Japan March 2021 - Calendar with holidays.