docs: public static String getSortKey(String str) {
  		StringBuilder ignoreChars = new StringBuilder();
  		StringBuilder tailCaps = new StringBuilder(str.length() + 1);
  		StringBuilder normChars = new StringBuilder(str.length() + 1 + tailCaps.capacity() + ignoreChars.capacity());
  		
  		for(int i=0; i<str.length(); i++) {
  			char ch = str.charAt(i);
  			
  			if( isIgnoredChar(ch) ) {
  				if( ch == 0x02BC ) {
  					ch = 0x2020;
  				}
  				ignoreChars.append(ch);
  				continue;
  			}
  			
  			
  			char lowerCh = Character.toLowerCase(ch);
  			
  			Character sortValue = UK_ALPHABET_MAP.get(lowerCh);
  			if (sortValue != null) {
  				normChars.append(sortValue);
  				tailCaps.append(ch);
  			}
  			else {
  				tailCaps.append(ch);
  			}
  			
  		}
  		
  		normChars.append(" ");
  		tailCaps.append(" ");
  		ignoreChars.append(" ");
  		
  		normChars.append(tailCaps);
  		normChars.append(ignoreChars);
  		
  		return normChars.toString();
  	}