org.apache.lucene.analysis.ru: public class: RussianCharsets

org.apache.lucene.analysis.ru
public class: RussianCharsets [javadoc | source]

java.lang.Object
   org.apache.lucene.analysis.ru.RussianCharsets

RussianCharsets class contains encodings schemes (charsets) and toLowerCase() method implementation for russian characters in Unicode, KOI8 and CP1252. Each encoding scheme contains lowercase (positions 0-31) and uppercase (position 32-63) characters. One should be able to add other encoding schemes (like ISO-8859-5 or customized) by adding a new charset and adding logic to toLowerCase() method for that charset.

version: $ - Id: RussianCharsets.java 564236 2007-08-09 15:21:19Z gsingers $

Field Summary
public static char[]	UnicodeRussian
public static char[]	KOI8
public static char[]	CP1251

Method from org.apache.lucene.analysis.ru.RussianCharsets Summary:
toLowerCase

Methods from java.lang.Object:
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method from org.apache.lucene.analysis.ru.RussianCharsets Detail:
public static char toLowerCase(char letter, char[] charset) { if (charset == UnicodeRussian) { if (letter >= '\u0430" && letter < = '\u044F") { return letter; } if (letter >= '\u0410" && letter < = '\u042F") { return (char) (letter + 32); } } if (charset == KOI8) { if (letter >= 0xe0 && letter < = 0xff) { return (char) (letter - 32); } if (letter >= 0xc0 && letter < = 0xdf) { return letter; } } if (charset == CP1251) { if (letter >= 0xC0 && letter < = 0xDF) { return (char) (letter + 32); } if (letter >= 0xE0 && letter < = 0xFF) { return letter; } } return Character.toLowerCase(letter); }

Method from org.apache.lucene.analysis.ru.RussianCharsets Detail:

 public static char toLowerCase(char letter,
    char[] charset) {
          
        if (charset == UnicodeRussian)
        {
            if (letter  >= '\u0430" && letter < = '\u044F")
            {
                return letter;
            }
            if (letter  >= '\u0410" && letter < = '\u042F")
            {
                return (char) (letter + 32);
            }
        }
        if (charset == KOI8)
        {
            if (letter  >= 0xe0 && letter < = 0xff)
            {
                return (char) (letter - 32);
            }
            if (letter  >= 0xc0 && letter < = 0xdf)
            {
                return letter;
            }
        }
        if (charset == CP1251)
        {
            if (letter  >= 0xC0 && letter < = 0xDF)
            {
                return (char) (letter + 32);
            }
            if (letter  >= 0xE0 && letter < = 0xFF)
            {
                return letter;
            }
        }
        return Character.toLowerCase(letter);
}