This is a Java client for the Automatic Certificate Management Environment (ACME) protocol as specified in RFC 8555.
ACME is a protocol that a certificate authority (CA) and an applicant can use to automate the process of verification and certificate issuance.
This Java client helps connecting to an ACME server, and performing all necessary steps to manage certificates.
It is an independent open source implementation that is not affiliated with or endorsed by Let's Encrypt.
- Fully RFC 8555 compliant
- Supports the
tls-alpn-01(RFC 8737) challenges
- Supports RFC 8738 IP identifier validation
- Supports RFC 8739 short-term automatic certificate renewal (experimental)
- Easy to use Java API
- Requires JRE 8 (update 101) or higher. For building the project, Java 9 or higher is required.
- Built with maven, packages available at Maven Central
- Requires jose4j, Bouncy Castle and slf4j as dependencies. If you have other means of generating key pairs and CSRs, you can even do without
acme4j-utilsand Bouncy Castle as dependency.
- Extensive unit and integration tests
- See the online documentation about how to use acme4j.
- For a quick start, have a look at the source code of an example.
acme4j is open source software. The source code is distributed under the terms of Apache License 2.0.
- I would like to thank Brian Campbell and all the other jose4j developers. acme4j would not exist without your excellent work.
- Thanks to Daniel McCarney for his help with the ACME protocol, Pebble, and Boulder.
- Ulrich Krause for his help to make acme4j run on IBM Java VMs.
- I also like to thank everyone who contributed to acme4j.
- JetBrains kindly provided a free open source license for IntelliJ IDEA.