Apex has testClassPattern - https://pmd.github.io/latest/pmd_rules_apex_codestyle.html#classnamingconventions

Java doesn't - https://pmd.github.io/latest/pmd_rules_java_codestyle.html#classnamingconventions

Having test classes names consistently end with "Test" is important to make sure they are correctly picked up by Maven Surefire plugin. I would say this is even more important than following other naming conventions.