Jackson Minor Version Compatibility checker

Background

Jackson project only guarantees cross-component compatibility within each minor release (that is, any combination of components with same minor version, regardless of patch version, should work without problems) (*).

But in practice project tries to retain some level of cross-minor-version compatibility between adjacent minor versions. This project is created to verify compatibility expectations.

(*) Note: user code that uses Jackson Public API has much stronger backward-compatibility guarantees -- code written against specific major version should remain working against all subsequent minor revisions: code that worked with 2.1, for example, should still work, without recompilation, against 2.9.

What is checked

This repository contains cross-minor-version tests for checking version compatibility between certain categories of minor versions, based on dependencies between Jackson components.

Specifically what is being checked is the case of:

• New versions of Jackson "core" components (annotations, streaming, databind)
• Old versions of:
  • Dataformat modules
  • (some) Datatype modules (guava, joda)
  • Other: JAXB annotation module

Notes on observed compatibility

Jackson 2.8

Jackson 2.9

Version 2.9 of core components appear compatiblity with dataformat and datatype modules of:

• 2.8
• 2.7

but does not work with version 2.6 or earlier.