jp.sourceforge.moreemacs/src/jp/sourceforge/moreemacs/utils/CharacterUtils.java

   1 package jp.sourceforge.moreemacs.utils;
   2
   3 import java.util.Arrays;
   4 import java.util.List;
   5 import java.util.Locale;
   6
   7 import com.ibm.icu.lang.UCharacter;
   8 import com.ibm.icu.lang.UProperty;
   9
  10 public final class CharacterUtils {
  11     private CharacterUtils() {}
  12
  13     private static List<String> EAST_ASIAN_LANGS =
  14         Arrays.asList("ja", "vi", "kr", "zh");
  15
  16     public static int getWidth(int codePoint) {
  17         return getWidth(codePoint, Locale.getDefault());
  18     }
  19
  20     public static int getWidth(int codePoint, Locale locale) {
  21         if(locale == null) {
  22             throw new NullPointerException("locale is null");
  23         }
  24         int value = UCharacter.getIntPropertyValue(codePoint,
  25                 UProperty.EAST_ASIAN_WIDTH);
  26         switch(value) {
  27         case UCharacter.EastAsianWidth.NARROW:
  28         case UCharacter.EastAsianWidth.NEUTRAL:
  29         case UCharacter.EastAsianWidth.HALFWIDTH:
  30             return 1;
  31         case UCharacter.EastAsianWidth.FULLWIDTH:
  32         case UCharacter.EastAsianWidth.WIDE:
  33             return 2;
  34         case UCharacter.EastAsianWidth.AMBIGUOUS:
  35             if(EAST_ASIAN_LANGS.contains(locale.getLanguage())) {
  36                 return 2;
  37             } else {
  38                 return 1;
  39             }
  40         default:
  41             return 1;
  42         }
  43     }
  44 }