void combine(FnObj &fn_obj)
{
intermediates_t intermediates;
intermediates.resize(num_partitions_);
using std::swap;
swap(intermediates_, intermediates);
for (auto const &intermediate : intermediates)
{
for (auto const &kv : intermediate)
{
fn_obj.start(kv.first);
for (auto const &value : kv.second)
fn_obj(value);
fn_obj.finish(kv.first, *this);
}
}
}
void combine(FnObj &fn_obj)
{
this->close_files();
for (intermediates_t::iterator it=intermediate_files_.begin(); it!=intermediate_files_.end(); ++it)
{
std::string infilename = it->second.first;
std::string outfilename = platform::get_temporary_filename();
// sort the input file
SortFn()(infilename.c_str(), outfilename.c_str(), 11);
boost::filesystem::remove(infilename);
std::swap(infilename, outfilename);
std::string key, last_key;
typename reduce_task_type::value_type value;
std::ifstream infile(infilename.c_str());
while (read_record(infile, key, value))
{
if (key != last_key && key.length() > 0)
{
if (last_key.length() > 0)
fn_obj.finish(last_key, *this);
if (key.length() > 0)
{
fn_obj.start(key);
std::swap(key, last_key);
}
}
fn_obj(value);
}
if (last_key.length() > 0)
fn_obj.finish(last_key, *this);
infile.close();
boost::filesystem::remove(infilename);
}
this->close_files();
}
