RTSJ Reference Implementation (RI) and Technology Compatibility Kit (TCK)

The RTSJ Reference Implementation (RI) defines Java technology conformance. The Technology Compatibility Kit (TCK) is the official test suite for the RTSJ. TimeSys is proud to be the Real-Time Specification for Java (RTSJ) Maintenance Lead, and to have built the official RI for the RTSJ.

Only TimeSys is authorized through the Java Community Process to maintain and modify the RTSJ and the TCK required to certify RTSJ compliance.

Login to download the RI and TCK now

The RI has moved to a new registration system (24 July 2006). The old database has not been transferred, so everyone will need to create a new profile and agree to the license again before they can download.


Enter a user name (which must be your email address) and press the New button to create a new profile or reset the password for an existing profile.

Note: User registration is necessary before you can download the RI and TCK. Your RI and TCK registration information will be shared with the RTSJ Maintenance Group.


TimeSys Reference Implementation/Technology Compatibility Kit Object Code License

Access the Specification

The Real Time Specification for Java can be viewed at www.rtsj.org or downloaded from jcp.org.

With TimeSys RTSJ-certified technology, you can:

  • Choose your own JVM platform
  • Take advantage of certified RTSJ-compliant technology used in commercial JVMs
  • Do it yourself or partner with experienced JVM developers
  • Customize your RTSJ implementation and deliver it to market faster
  • Freely access commercial qualities RI binaries and TCK binaries for the X86 platform
  • Enable multiple developers to leverage the technology on multiple projects (for non-commercial research use only)