Oracle is touting a “tip and tail” model for Java library development that the company says would give application developers a better experience and at the same time help library developers innovate faster.

The JEP (JDK Enhancement Proposal) created September 30 and updated October 7 describes a release model for software libraries. The “tip” release of a library contains new features and bug fixes, the proposal states, while “tail” releases contain only critical bug fixes. As little as possible is backported from the tip to the tails. The JDK itself has used tip and tail since 2018 to deliver new features at a faster pace and provide reliable, predictable updates focused on stability. Goals of the plan include:

  • Helping the Java ecosystem maintain the balance between innovating rapidly for new development and ensuring stability for long-term developments.
  • Recognizing that application developers have diverse views about changes to make it necessary to update libraries and the JDK.
  • Ensuring library developers do not have to choose between supporting users of older JDKs and embracing new features, such as virtual threads and patterns, that excite users of newer JDKs.
  • Not constraining library release cycles, version schemes, or bad choices.

In explaining the motivation behind the proposal, the proposal states that the tip and tail model is a streamlined form of the multi-train model, which lets libraries serve a diverse user base while embracing new Java features. Tip and tail gives users focused on stability what they need, namely fixes and patches, while giving users building new systems what they want, namely features and enhancements, at a faster pace. The tip and tail model will keep the Java platform an attractive choice for new applications while safeguarding the future of existing applications, the proposal stresses.