Generic.hh

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 
#ifndef avro_Generic_hh__
#define avro_Generic_hh__
 
#include <boost/utility.hpp>
 
#include "Config.hh"
#include "Decoder.hh"
#include "Encoder.hh"
#include "GenericDatum.hh"
#include "Types.hh"
 
namespace avro {
class AVRO_DECL GenericReader : boost::noncopyable {
    const ValidSchema schema_;
    const bool isResolving_;
    const DecoderPtr decoder_;
 
    static void read(GenericDatum &datum, Decoder &d, bool isResolving);
 
public:
    GenericReader(ValidSchema s, const DecoderPtr &decoder);
 
    GenericReader(const ValidSchema &writerSchema,
                  const ValidSchema &readerSchema, const DecoderPtr &decoder);
 
    void read(GenericDatum &datum) const;
 
    void drain() {
        decoder_->drain();
    }
    static void read(Decoder &d, GenericDatum &g);
 
    static void read(Decoder &d, GenericDatum &g, const ValidSchema &s);
};
 
class AVRO_DECL GenericWriter : boost::noncopyable {
    const ValidSchema schema_;
    const EncoderPtr encoder_;
 
    static void write(const GenericDatum &datum, Encoder &e);
 
public:
    GenericWriter(ValidSchema s, EncoderPtr encoder);
 
    void write(const GenericDatum &datum) const;
 
    static void write(Encoder &e, const GenericDatum &g);
 
    static void write(Encoder &e, const GenericDatum &g, const ValidSchema &) {
        write(e, g);
    }
};
 
template<typename T>
struct codec_traits;
 
template<>
struct codec_traits<std::pair<ValidSchema, GenericDatum>> {
    static void encode(Encoder &e,
                       const std::pair<ValidSchema, GenericDatum> &p) {
        GenericWriter::write(e, p.second, p.first);
    }
 
    static void decode(Decoder &d, std::pair<ValidSchema, GenericDatum> &p) {
        GenericReader::read(d, p.second, p.first);
    }
};
 
template<>
struct codec_traits<GenericDatum> {
    static void encode(Encoder &e, const GenericDatum &g) {
        GenericWriter::write(e, g);
    }
 
    static void decode(Decoder &d, GenericDatum &g) {
        GenericReader::read(d, g);
    }
};
 
} // namespace avro
#endif