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Eclipse Yasson

Eclipse Yasson is a Java library that implements the Jakarta JSON Binding (JSON-B) specification for mapping between Java objects and JSON data.

  • Reference implementation of Jakarta JSON Binding (JSON-B) for Java (data binding)
  • Object-to-JSON and JSON-to-object mapping for Java classes (serialization/deserialization)
  • Configurable mapping behavior via JSON-B configuration and annotations (configuration/metadata)
  • Support for integration with other Jakarta EE components and runtimes (Jakarta EE platform)
  • Extensible mechanisms for custom serializers, deserializers, and adapters (extensibility)

More About Eclipse Yasson

Eclipse Yasson is the reference implementation of the Jakarta JSON Binding (JSON-B) specification, which defines a standard way to convert between Java objects and JSON documents in Jakarta EE and Java applications (data binding).

The project addresses the problem of consistent, specification-based JSON mapping across different Java runtimes and libraries, providing a uniform Application Programming Interface (API) for serialization and deserialization of Java object graphs to and from JSON (application integration). By implementing the JSON-B specification, Eclipse Yasson enables developers to use a standard programming model, independent of any particular application server or vendor (interoperability).

Core capabilities of Eclipse Yasson include object-to-JSON and JSON-to-object mapping, support for Java types such as collections and generics, and handling of structured object graphs (data mapping). It supports both default mapping rules and explicit control through annotations such as those defined by JSON-B, allowing configuration of property names, formatting of dates and numbers, inclusion or exclusion of fields, and handling of null values (configuration/metadata).

Yasson exposes configuration options via the JSON-B configuration API, enabling tuning of behaviors such as property visibility, naming strategies, and formatting (runtime configuration). It also supports adapters, custom serializers, and custom deserializers so that applications can integrate domain-specific logic into the binding process, for example when interfacing with existing JSON formats or external services (extensibility).

In enterprise environments, Eclipse Yasson is used within Jakarta EE stacks and Java-based services where JSON is the interchange format for RESTful endpoints, messaging, or configuration (enterprise application integration). Because it adheres to the Jakarta JSON Binding specification, it can be combined with other Jakarta EE technologies, such as RESTful web services frameworks, to provide end-to-end JSON processing with a common programming model (Jakarta EE platform).

From an architectural perspective, Yasson operates as a library that applications or frameworks embed, instantiated through the JSON-B API to perform marshalling and unmarshalling between Java objects and JSON payloads (middleware component). It fits into directories and taxonomies under categories such as JSON data binding, Jakarta EE reference implementations, and Java serialization frameworks. For organizations standardizing on Jakarta EE or interoperable Java stacks, Eclipse Yasson provides the specification-compliant JSON-B layer required for consistent JSON handling across services and components (standard-based integration).