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/*
* Copyright (C) 2015 Canonical Ltd.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 3 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Authored by: Michi Henning <michi.henning@canonical.com>
*/
#include <core/persistent_cache.h>
#include <iostream>
#include <sstream>
#include <string>
using namespace std;
struct Person
{
string name;
int age;
};
namespace core // Specializations must be placed into namespace core.
{
template <>
string CacheCodec<Person>::encode(Person const& p)
{
ostringstream s;
s << p.age << ' ' << p.name;
return s.str();
}
template <>
Person CacheCodec<Person>::decode(string const& str)
{
istringstream s(str);
Person p;
s >> p.age >> p.name;
return p;
}
} // namespace core
#define DB_NAME "person_db"
int main(int /* argc */, char** /* argv */)
{
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-result"
system("rm -fr " DB_NAME "/*");
#pragma GCC diagnostic pop
using PersonCache = core::PersistentCache<Person, string>;
auto c = PersonCache::open(DB_NAME, 1024 * 1024 * 1024, core::CacheDiscardPolicy::lru_only);
Person bjarne{"Bjarne Stroustrup", 65};
c->put(bjarne, "C++ inventor");
auto value = c->get(bjarne);
if (value)
{
cout << bjarne.name << ": " << *value << endl;
}
Person person{"no such person", 0};
value = c->get(person);
assert(!value);
}
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