protected Comparator getComparator(int column) {
        Class columnType = tableModel.getColumnClass(column);
        Comparator comparator = (Comparator) columnComparators.get(columnType);
        
        // カラム名取得（カラム名によってソートcomparatorを切り替える）
        String columnName = tableModel.getColumnName(column);
        if ( columnName.equals(SearchPage.COL_LABEL_SCORE) ) {
        	return STRING_DOUBLE_COMPARATOR;
        }
        else if ( columnName.equals(SearchPage.COL_LABEL_HIT)
        		|| columnName.equals(SearchPage.COL_LABEL_NO)
        		|| columnName.equals(SearchPage.COL_LABEL_ORDER)) {
        	return INTEGER_COMPARATOR;
        }
        else if ( columnName.equals(SearchPage.COL_LABEL_MATCH)) {
        	return STRING_INTEGER_COMPARATOR;
        }
        
        if (comparator != null) {
            return comparator;
        }
        if (Comparable.class.isAssignableFrom(columnType)) {
            return COMPARABLE_COMAPRATOR;
        }
        return LEXICAL_COMPARATOR;
    }