calligra-l10n-ja software package provides Japanese (ja) localization files for Calligra, you can install in your Ubuntu 16.04 LTS (Xenial Xerus) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install calligra-l10n-ja
calligra-l10n-ja is installed in your system.
Make ensure the calligra-l10n-ja package were installed using the commands given below,
$ sudo dpkg-query -l | grep calligra-l10n-ja *
You will get with calligra-l10n-ja package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | KDE |
| Package | calligra-l10n-ja |
| Version | 1:2.9.5-0ubuntu2 |
| Description | Japanese (ja) localization files for Calligra |
| Sub Section | KDE |