concordia-library/concordia/regex_rule.cpp

#include "concordia/regex_rule.hpp"
#include <sstream>
#include <iostream>
#include <boost/exception/all.hpp>
#include <boost/throw_exception.hpp>

RegexRule::RegexRule(std::string patternString,
                     int annotationType,
                     std::string value,
                     bool caseSensitive)
                             throw(ConcordiaException):
                               _annotationType(annotationType),
                               _value(value)                  {
    try {
        if (caseSensitive) {
            _pattern = boost::make_u32regex(UnicodeString(patternString.c_str()));
        } else {
            _pattern = boost::make_u32regex(UnicodeString(patternString.c_str()), boost::regex::icase);
        }
    } catch(const std::exception & e) {
        std::stringstream ss;

        ss << "Bad regex pattern: " << patternString <<
             " Detailed info: " << e.what();

        if (std::string const * extra =
                 boost::get_error_info<my_tag_error_info>(e) ) {
            ss << *extra;
        }
        throw ConcordiaException(ss.str());
    }
}

RegexRule::~RegexRule() {
}

void RegexRule::apply(boost::shared_ptr<TokenizedSentence> sentence) {
    try {
        UnicodeString s(sentence->getSentence().c_str());
        boost::u32regex_iterator<const UChar*> begin(boost::make_u32regex_iterator(s, _pattern));
        boost::u32regex_iterator<const UChar*> end;
        std::vector<TokenAnnotation> annotations;
        for (; begin != end; ++begin) {
            SUFFIX_MARKER_TYPE matchBegin = begin->position();
            SUFFIX_MARKER_TYPE matchEnd = matchBegin + begin->length();
            std::string value;
            if (_annotationType == TokenAnnotation::WORD) {
                UnicodeString unicodeValue;
                s.extract(begin->position(), begin->length(), unicodeValue); 
                unicodeValue.toUTF8String(value);
            } else {
                value = _value;
            }
            TokenAnnotation annotation(matchBegin, matchEnd, _annotationType, value);
            annotations.push_back(annotation);
        }
        sentence->addAnnotations(annotations);
    } catch(const std::exception & e) {
        std::stringstream ss;
        ss << "Exception while applying regex rule: "
                          << _annotationType << " to text: " << sentence->getSentence();
        ss << ", message: " << e.what();
        throw ConcordiaException(ss.str());
    }
}