The JSON-B is a new standard that maps Java types to and from JSON structures, respectively. Similarly to JAXB for XML, it provides functionality to declaratively map objects.

The biggest advantage of this standard within the Java EE ecosystem is that applications don't need to rely on vendor-specific implementations anymore. JSON mapping frameworks have typically prevented enterprise applications to be built in a portable way. They increase the risk of breaking runtime dependencies with existing framework versions.

JSON-B solves this issue by providing standardized JSON mapping. Shipping custom mapping frameworks such as Jackson or Johnzon is not required anymore.