To avoid code duplication I come up with the following solution (the common logic might be more complicated, I simplified it for the sake of brevity):

interface Mapper {     void saveOne(Map<String, Object> params);     void saveTwo(Map<String, Object> params); }  public class Main {     private static final Mapper mapper = new MapperImpl();      public static void main(String[] args) {         saveOne();         saveTwo();     }      private static void saveOne() {         save(new HashMap<>(Map.of("num", "one")), mapper::saveOne);     }      private static void saveTwo() {         save(new HashMap<>(Map.of("num", "two")), mapper::saveTwo);     }      private static void save(Map<String, Object> params, Consumer<Map<String, Object>> consumer) {         params.put("name", "Some Name");         params.put("type", "Some Type");         consumer.accept(params);     } }  class MapperImpl implements Mapper {     @Override     public void saveOne(Map<String, Object> params) {         System.out.println("Saving one with params: " + params);     }      @Override     public void saveTwo(Map<String, Object> params) {         System.out.println("Saving two with params: " + params);     } } 

Is the above approach viable, readable, and clean?

Or, it will be better to rewrite it without lambdas and method references:

public static void main(String[] args) {     saveOne();     saveTwo(); }  private static void saveOne() {     Map<String, Object> params = new HashMap<>();     params.put("num",  "one");     params.put("name", "Name 1");     params.put("type", "Type 1");     mapper.saveOne(params); }  private static void saveTwo() {     Map<String, Object> params = new HashMap<>();     params.put("num",  "two");     params.put("name", "Name 2");     params.put("type", "Type 2");     mapper.saveTwo(params); } 

Which one is better in terms of functionality, purity, and readability?