Jandex

Jandex is a space efficient Java class file indexer and offline reflection library.

It supports:

  • Indexing a set of classes into a memory efficient representation

  • Browsing and searching for annotations, including Java 8 type annotations

  • Browsing and searching for declarations and types, including generic type information

  • Browsing and searching through the class and interface inheritance hierarchy

  • Persisting an index in a custom storage efficient format and fast loading of that format

  • Compatibility with previous API and storage format versions, as described in the Compatibility Promise

  • Execution via API, command line tool, Ant, and Maven plugin

Remember that Jandex has extensive API documentation in the javadoc form. This documentation site is currently rather incomplete, so please consult the javadoc frequently.

Requirements

Jandex 3.0+ requires Java 8 to run.

The runtime Java version does not affect the Jandex bytecode parsing capabilities. Jandex running on Java 8 can still parse Java 17 bytecode.

Getting Help

Issues can be reported in GitHub Issues.

For discussions, use the SmallRye Google Group or the Quarkus Zulip chat.

Compatibility Promise

Jandex uses an X.Y.Z versioning scheme. In the following text, we call X a major version, Y a minor version, and Z a micro version.

API

Jandex may break backward compatibility for callers of the Jandex API in major versions. If you only call Jandex API, updating to a newer minor or micro version is safe.

Jandex may break backward compatibility for users that extend Jandex classes or implement Jandex interfaces in minor or major versions. If you extend Jandex classes or implement Jandex interfaces, updating to a newer micro version is safe.

Persistent Index Format

The persistent index format is versioned. Jandex is backward compatible when it comes to reading the persistent index, but not forward compatible. In other words, newer Jandex can read older index, but older Jandex can’t read newer index.

Jandex may introduce a new persistent index format version in minor or major versions. If you distribute a Jandex index as part of your artifacts, updating to a newer micro version is safe. Updating to a newer minor or major version may require consumers of the Jandex index to also update.

Persistent Index Format Versions

For reference, this table shows which Jandex version produces which persistent format version by default. It is also a maximum persistent index format version the given Jandex version can read.

Jandex version Persistent format version

Jandex 3.2.x

12

Jandex 3.0.x, 3.1.x

11

Jandex 2.4.x

10

Jandex 2.1.1+, 2.2.x, 2.3.x

9

Jandex 2.1.0

8 (version 7 only in Jandex 2.1.0.Beta1 and Beta2)

Jandex 2.0.x

6