JCR Java

A Java implementation of JSON Content Rules (JCR).


A faithful Java implementation of JCR.

If done right, this could hopefully become the replacement reference implementation. The current reference implementation is JCRValidator, a Ruby implementation. JCRValidator is a Ruby implementation that uses Parslet, a PEG parser, to parse the JCR syntax.

This implementation uses a hand-built parser that more closely follows the official ABNF.

It is also hoped that this implementation can be more performant for JSON evaluations by using Java 8 lambdas and Java threads. Therefore this is targeting Java 8 (and above).

Current Status

This is in the very preliminary stages, and is not at all usable.

At present, the parser framework is laid out and parsing most of the basic JCR syntax. The following are a list of tasks left to do:

  • parsing of directives
  • mapping of target rule names
  • checking of subgroups to arrays and objects
  • validation of primitives
  • validation of arrays
  • validation of members
  • validation of groups
  • ...
  • tie it altogether


Java 8 is required to build and run the tests. Specifically, a JDK (not just a JRE). Installing that is platform dependent, and if you have other versions of Java installed you'll need to understand how to run multiple versions of Java simultaneously (some systems have various means for this ). At the very least, java and javac should be in your shell's executable path and it may be required that your shell have a JAVA_HOME environment variable pointing the installation of the Java 8 JDK.

From there, building and running the tests is as follows.

For Linux, MacOS and Unix styled OS, use the Gradle wrapper shell script:

./gradlew clean build

For Windows, use the Gradle wrapper batch script:

gradlew.bat clean build


For more information on JCR: