JSON-B, the JSON binding library expected to be added to Java EE 8, has been released for public review. The library builds on top of JSON Processing (not to be confused with JSONP or JSON-with-padding), and intends to provide a standard alternative to popular libraries such as Jackson or Gson. The JSR is only targeted for inclusion in Java EE though, meaning users of Java SE will still need to make use of external libraries.
The JSON Processing library was added to Java EE 7 in 2013 in order to provide an API for JSON manipulation. Although JSON-P is useful to navigate and construct a JSON object, it has proven insufficient in satisfying the day-to-day needs of developers, who required an easier and more transparent way to convert a common Java object into JSON and vice versa.
In addition to representing only a partial solution, JSON Processing appeared after a number of third party tools had already emerged, among them Gson in 2008 and Jackson in 2009. These tools provide several integration mechanisms to interact with other Java EE components like JAX-RS, which makes them very popular in web application development. However, the spread of different available technologies makes it difficult to create portable applications, and the need for a standardised solution has become apparent. This was reflected in the Java EE 8 Community Survey of 2014, where a JSON binding tool was voted the highest priority for a new Java EE release. Given this, the JSR for JSON-B was created in August of that very year, with the intention of releasing it in the first half of 2017.
Despite the strong demand in the community for this kind of functionality, the library faces a number of risks that could prevent its adoption. On one hand, JSON Binding may be appearing just too late: the current plan of releasing in 2017 already implies a six months delay from the original schedule, which has translated into a six months delay of Java EE 8 itself. Not only this, the current schedule implies a delay of seven years with regards to the industry.
On the other hand, and as Tatu Saloranta, lead developer of Jackson, pointed out, the fact that JSON Binding is based in JSON Processing imposes limitations in its scope and extensibility. Saloranta discussed the possibility of re-implementing Jackson on top of JSON-B to try and make use of the new standard, but almost immediately discarded the possibility:
Both make it difficult to, for example, make Jackson implement or be based on JSON-B. In addition to the whole licensing limbo, the limited scope and extensibility means that much of what Jackson does, beyond simple JSON databinding, could not be exposed in a compatible manner.
The potentially reduced benefits of JSON-B adds weight to the mounting concerns that Java EE is not receiving enough attention, as was reflected in the minutes of a recent meeting of the JCP Executive Committee, and may contribute to transferring responsibilities over Java EE development to the community.
