JXXON — C++ JSON object mapper library

Serialize C++ object hierarchies into JSON documents and vice versa almost as conveniently as Java objects using Jackson.

Design goals

Focus on one thing and do that well

Mapping C++ object hierarchies and containers to JSON documents. There are a couple of C++ JSON parsers/generators out there, mature and proven. I will not attempt to write a better one. Instead, JXXON relies on existing ones.

Full encapsulation

JXXON does not expose any details of the encapsulated JSON parsers/generators to clients. Neither explicitly, nor via transitive inclusion.

Polymorphism-friendliness

Providing a common interface base class, which all serializable classes are to implement.

Lacking such an interface, object mapper consumer classes supposed to handle more than one type would be forced to a non-polymorphic design, using non-virtual template member functions, or using member overloads. In any case, sacrificing all object oriented runtime flexibility.

Concise handling of null values

Throwing exceptions, when there is a null value somewhere in JSON input, is probably the least helpful thing to do. Null values are valid JSON, even when they occur as array elements.

Integrate C++ standard containers as transparently as possible and to a reasonable extent.

C++ standard containers should feel like first class citizens in JSON. Based on a little bit of wrapping.

Thorough testing

Best practice rather than strictly a design goal. A templatized test suite helps boosting code and branch coverage to amazing levels.

Example

#include "JXXON/Serializable.h"
#include <string>

struct SampleObject : public JXXON::Serializable
{
        // Deserializing constructor
        SampleObject(const JXXON::Json &json) :
                property(json.get<decltype(property)>("property_name")),
        {
        }

        // Serializing virtual function
        virtual JXXON::Json toJson() const override
        {
                JXXON::Json json;
                json.set("property_name", property);
                return json;
        }

        // Non-nullable field.
        std::string property;
};

Modern C++ under the hood

Template templates with parameter packs
Smart pointers
Lambda expressions
Range loops

Dependencies

JXXON is using Polymorphic decorators >= 1.2.0 to extend C++11 standard containers and to add serializability.

Processing of JSON documents is delegated to either JsonCpp >= 1.6.0 or Poco >= 1.7.4, depending on your choice when building the JXXON library.

License

Free Software, licensed under the Boost Software License.

jxx-project/JXXON