The old system stored a list of letters per score:

1 point: "A", "E", "I", "O", "U", "L", "N", "R", "S", "T",

2 points: "D", "G",

3 points: "B", "C", "M", "P",

4 points: "F", "H", "V", "W", "Y",

5 points: "K",

8 points: "J", "X",

10 points: "Q", "Z",

The shiny new scrabble system instead stores the score per letter, which makes it much faster and easier to calculate the score for a word. It also stores the letters in lower-case regardless of the case of the input letters:

"a" is worth 1 point.

"b" is worth 3 points.

"c" is worth 3 points.

"d" is worth 2 points.


Your mission, should you choose to accept it, is to write a program that transforms the legacy data format to the shiny new format.


import java.util.Map;
import java.util.List;
import java.util.HashMap;

import com.google.inject.AbstractModule;

public class Etl extends AbstractModule {
  public Map transform(Map<Integer, List<String>> oldData) {
    Map<String, Integer> items = new HashMap<String, Integer>();

    for(Map.Entry<Integer, List<String>> entry: oldData.entrySet()) {
      for(String chr: entry.getValue()) {
       items.put(chr.toLowerCase(), entry.getKey()); 
    return items;

Can the above code be made more readable and optimized?


2 Answers 2


One way to improve readability is through the naming of your variables.

  • oldData can be called something like pointsMap or pointsGroups
  • items can be called result or characterPoints
  • entry can be called pointGroup
  • chr can be called character (and would as the other answer suggests be better of as a Character and not String)

Additionally, your class is called Etl which I just have no clue what that's supposed to mean. I'm also not sure why it extends AbstractModule.

Also, your transform method can be static


The two things I would change:

  • The Map you're returning should have type parameters.
  • The key is best to be a Character rather than a String.

Other than that, I don't see much more to it than what you've got there already.


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