A local variable assigned only once can be declared final. LocalVariableCouldBeFinal (Priority: 3, Ruleset: Code Style) https://docs.pmd-code.org/snapshot/pmd_rules_java_codestyle.html#localvariablecouldbefinal

Unused Private Method detects when a private method is declared but is unused. UnusedPrivateMethod (Priority: 3, Ruleset: Best Practices) https://docs.pmd-code.org/snapshot/pmd_rules_java_bestpractices.html#unusedprivatemethod

Reports method and constructor parameters that can be made final because they are never reassigned within the body of the method. This rule ignores unused parameters so as not to overlap with the rule {% rule java/bestpractices/UnusedFormalParameter %}. It will also ignore the parameters of abstract methods. MethodArgumentCouldBeFinal (Priority: 3, Ruleset: Code Style) https://docs.pmd-code.org/snapshot/pmd_rules_java_codestyle.html#methodargumentcouldbefinal