Azul Zulu Builds of OpenJDK and other OpenJDK installation packages do not include any font files by default. But both automatically use available fonts provided by the Operating System as high quality TTF files.
On headless servers or small Linux installations like containers or embedded systems those operating system font packages are usually not installed by default. Here the commands to install a standard set of them:
RHEL / Centos:
sudo yum install fontconfig dejavu-sans-fonts dejavu-serif-fonts
Ubuntu / Debian:
sudo apt install fonts-dejavu fontconfig
sudo zypper install dejavu-fonts fontconfig
Desktop Operating Systems like Windows and macOS usually already have many fonts in TTF format already installed by default and don't require additional installations.
After installation of those font packages, Azul Zulu Builds of OpenJDK will automatically use the TTF files provided by the packages. If an application asks for specific font names, like for example Lucida, the fontconfig package installed with the commands above provides a similar replacement font without the need for a change in the application code.
Some applications require certain language-specific fonts. Those are usually also available by most operating systems, either by other font package names or language packs. Here a few starting points, for further details please refer to your Operating System documentation:
- Language Packs for Windows
Make sure not to enable "Set as my display language" as that would change your desktop language and could lock you out with unreadable text.
- Ubuntu Linux, command to search for other font packages:
apt search ^fonts-
- RHEL/CentOS 7, command to install a larger group of international fonts:
sudo yum groupinstall Fonts
Below you see an example error message shown by Java applications when fonts are missing in your operating system. Another indicator that fonts are missing are rectangle symbols shown instead of normal text. Both problems can usually be solved by installing the font packages as described above.
Exception in thread "main" java.lang.Error: Probable fatal error:No fonts found.
If you don't see such an error message but the font rendering appears to be low quality, please also follow the instructions listed above as some TTF files might be missing on the system. If after the installation the font rendering appears to be still unexpected, take a look at Font rendering changes after upgrading Azul Zulu Builds of OpenJDK.