Question

I am working at the moment with some data in hungarians.
I have to sort a list of hungarians strings.

According to this Collation Sequence page

Hungarian alphabetic order is: A=Á, B, C, CS, D, DZ, DZS, E=É, F, G,
GY, H, I=Í, J, K, L, LY, M, N, NY, O=Ó, Ö=Ő, P, Q, R, S, SZ, T, TY,
U=Ú, Ü=Ű, V, W, X, Y, Z, ZS

So vowels are treated the same (A=Á, …) so in the result you can have some like that using Collator :

Abdffg
Ádsdfgsd
Aegfghhrf

Up to here, no problem 🙂

But now, I have the requirement to sort according to the Hungarian alphabet

A Á B C Cs D Dz Dzs E É F G Gy H I Í J K L Ly M N Ny O Ó Ö Ő P (Q) R S
Sz T Ty U Ú Ü Ű V (W) (X) (Y) Z Zs

A is considered different than Á

Playing with the Strength from Collator doesnt change the order in the output. A and Á are still mixed up.

Is there any librairies/tricks to sort a list of string according to the hungarian alphabetical order?

So far what I am doing is :

• Sort with Collator so that the C/Cs, D,DZ, DZS… are sorted correctly
• Sort again by comparing the first characters of each word based on a map

This looks too much hassle for the task no?

List<String> words = Arrays.asList(
        "Árfolyam", "Az",
        "Állásajánlatok","Adminisztráció",
        "Zsfgsdgsdfg", "Qdfasfas"

);

final Map<String, Integer> map = new HashMap<String, Integer>();
      map.put("A",0);
      map.put("Á",1);
      map.put("E",2);
      map.put("É",3);

      map.put("O",4);
      map.put("Ó",5);
      map.put("Ö",6);
      map.put("Ő",7);

      map.put("U",8);
      map.put("Ú",9);
      map.put("Ü",10);
      map.put("Ű",11);


      final Collator c = Collator.getInstance(new Locale("hu"));
      c.setStrength(Collator.TERTIARY);
      Collections.sort(words, c);

      Collections.sort(words, new Comparator<String>(){
          public int compare(String s1, String s2) {

              int f = c.compare(s1,s2);
              if (f == 0) return 0;

              String a = Character.toString(s1.charAt(0));
              String b = Character.toString(s2.charAt(0));

              if (map.get(a) != null && map.get(b) != null) {
                  if (map.get(a) < map.get(b)) {
                      return -1;
                  }
                  else if (map.get(a) == map.get(b)) {
                      return 0;
                  }
                  else {
                      return 1;
                  }
              }


              return 0;
          }
      });

Thanks for your input

Answer 1

I found a good idea, you can use a RuleBasedCollator.

Source: http://download.oracle.com/javase/tutorial/i18n/text/rule.html

And here is the Hungarian rule:

 < a,A < á,Á < b,B < c,C < cs,Cs,CS < d,D < dz,Dz,DZ < dzs,Dzs,DZS 
 < e,E < é,É < f,F < g,G < gy,Gy,GY < h,H < i,I < í,Í < j,J
 < k,K < l,L < ly,Ly,LY < m,M < n,N < ny,Ny,NY < o,O < ó,Ó 
 < ö,Ö < ő,Ő < p,P < q,Q < r,R < s,S < sz,Sz,SZ < t,T 
 < ty,Ty,TY < u,U < ú,Ú < ü,Ü < ű,Ű < v,V < w,W < x,X < y,Y < z,Z < zs,Zs,ZS