You don't need to install Java 8 (on Linux)

[ddsnowboard]

If you're running this on Linux and don't want to downgrade your Java all the way to Java 8, you can avoid it using these steps:

1. Go download the JRE tar for your platform here: https://github.com/adoptium/temurin8-binaries/releases/tag/jdk8u422-b05. You want the one that starts with "OpenJDK8U-jre_"
2. Unzip that (tar -zxf $FILENAME.tar.gz, if you don't know) anywhere you want.
3. Run the bash script to install CTAT like INSTALL4J_JAVA_HOME_OVERRIDE=JRE_PATH_GOES_HERE bash CTAT_unix_4_4_0.sh, where JAR_PATH_GOES_HERE is the absolute path to the JRE folder you unzipped in step 2. It very likely ends with jdk8u422-b05-jre or something similar.
4. That should run normally. Once you're done, there should be a new CTAT folder in your home directory. You can run the Java applets in that folder from the terminal if you prepend them with INSTALL4J_JAVA_HOME_OVERRIDE=JRE_PATH_GOES_HERE just like before (so something like INSTALL4J_JAVA_HOME_OVERRIDE=JRE_PATH_GOES_HERE bash "CTAT for Java").