code: package com.google.checkstyle.test.chapter5naming.rule526parameternames;
  
  import java.util.function.BiFunction;
  import java.util.function.Function;
  
  public class InputLambdaParameterName {
  
      Function<String, String> badNamedParameterWithoutParenthesis =
              S -> S.trim().toLowerCase(); // warn
  
      Function<String, String> badNamedParameterWithParenthesis =
              (sT) -> sT.trim().toLowerCase(); // warn
  
      BiFunction<String, String, String> twoBadNamedParameters = (sT1, sT2) -> sT1 + sT2; // warn
  
      BiFunction<String, String, String> badNamedParameterInBiFunction =
              (first, _s) -> first + _s; // warn
  
      Function<String, Integer> goodNamedParameterWithoutParenthesis =
              notTrimmedString -> notTrimmedString.trim().length();
  
      Function<String, Integer> goodNamedParameterWithParenthesis =
              (notTrimmedString) -> notTrimmedString.trim().length();
  
      BiFunction<String, String, Integer> goodNamedParameters =
              (first, second) -> (first + second).length();
  
  }
  