The OpenJDK project has published a proposal called JEP 540, which would give Java a built-in tool for reading and writing JSON documents. Published on 2026-07-23 GMT, the proposal is still in an early stage known as incubation, meaning the design could change before it becomes a permanent part of Java. (OpenJDK)

JSON is a plain-text format for organizing data in a way that both humans and computers can read. If you have ever looked at a file with curly braces, quoted labels, and comma-separated values, that was likely JSON. It is the most common way that apps and websites send information back and forth.

This is not the first time someone tried to add JSON support directly to Java. A similar proposal called JEP 198 was written in 2014 but never made it into the final product. Since then, Java developers have had to rely on third-party tools — external pieces of software they download separately — to handle JSON.

The goal of the new proposal is modest. It wants Java itself to be able to read and produce standard JSON, nothing more. It deliberately leaves out advanced features like automatically converting JSON into Java objects, handling very large files in chunks, or offering multiple ways to configure how parsing works.

The proposal also takes a strict approach to what counts as valid JSON. It follows a specification called RFC 8259, which is the official rulebook for the JSON format. If a file does not follow those rules exactly, the built-in tool will reject it. Some popular third-party tools are more forgiving — they accept JSON with comments, trailing commas, or other non-standard additions. This new API will not do that.

The proposal names several well-established JSON tools in the Java world: Jackson, Gson, Jakarta JSON Processing, Jakarta JSON Binding, and Fastjson 2. It explicitly states that it does not aim to replace them. These tools offer features that production applications depend on, and the new built-in option is not trying to compete on that level. Think of it like the basic calculator app on your phone: it handles everyday math, but if you need a spreadsheet with formulas and charts, you open a different program.

The decision to incubate the API means the design is not yet frozen. Incubating features ship with a label that warns developers the API might change. Anyone who uses it before it is finalized accepts the risk that their code may need updating later.

The broader context here is that JSON has been the most widely used data format for over fifteen years, and Java has never included a native tool for it. The platform has long had built-in support for XML, an older data format that JSON largely replaced. As JSON took over, the gap in Java's standard toolkit became more noticeable.

For someone who just needs to read a JSON configuration file or send a simple JSON response from a small program, the proposed built-in tool could make life easier by removing the need to download a separate library. For anything more complex, the established tools remain the better choice.

The design is still open. Developers who care about how this tool takes shape have a chance to weigh in through the standard OpenJDK feedback channels before it is finalized.