A tool for checking backward API/ABI compatibility of a Java library
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Java API Compliance Checker (JAPICC) — a tool for checking backward binary and source-level compatibility of a Java library API.


  1. About
  2. Install
  3. Usage
  4. Test suite


The tool checks classes declarations of old and new versions and analyzes changes that may break compatibility: removed methods, removed class fields, added abstract methods, etc. The tool is intended for developers of software libraries and Linux maintainers who are interested in ensuring backward compatibility.

The Scala language is supported since 1.7 version of the tool.

Java 9 is supported since 2.4 version of the tool.

The tool is a core of the Java API Tracker project: https://abi-laboratory.pro/java/tracker/


sudo make install prefix=/usr
  • JDK or OpenJDK - development files
  • Perl 5


japi-compliance-checker OLD.jar NEW.jar
Java 9
japi-compliance-checker OLD.jmod NEW.jmod
Create API dumps
japi-compliance-checker -dump LIB.jar -dump-path ./API.dump
japi-compliance-checker API-0.dump API-1.dump
Adv. usage

For advanced usage, see doc/index.html or output of -help option.

Test suite

The tool is tested properly in the Java API Tracker project, by the community and by the internal test suite:

japi-compliance-checker -test

There are about 100 basic tests in the test suite.