Reassigning loop variables can lead to hard-to-find bugs. Prevent or limit how these variables can be changed. In foreach-loops, configured by the `foreachReassign` property: - `deny`: Report any reassignment of the loop variable in the loop body. _This is the default._ - `allow`: Don't check the loop variable. - `firstOnly`: Report any reassignments of the loop variable, except as the first statement in the loop body. _This is useful if some kind of normalization or clean-up of the value before using is permitted, but any other change of the variable is not._ In for-loops, configured by the `forReassign` property: - `deny`: Report any reassignment of the control variable in the loop body. _This is the default._ - `allow`: Don't check the control variable. - `skip`: Report any reassignments of the control variable, except conditional increments/decrements (`++`, `--`, `+=`, `-=`). _This prevents accidental reassignments or unconditional increments of the control variable._ AvoidReassigningLoopVariables (Priority: 3, Ruleset: Best Practices) https://docs.pmd-code.org/pmd-doc-7.7.0/pmd_rules_java_bestpractices.html#avoidreassigningloopvariables