Philadelphia FIX 4.1 implements the FIX protocol version 4.1.
Add a Maven dependency to Philadelphia FIX 4.1:
<dependency>
<groupId>com.paritytrading.philadelphia</groupId>
<artifactId>philadelphia-fix41</artifactId>
<version><!-- latest release --></version>
</dependency>
See the latest release on GitHub.
Released under the Apache License, Version 2.0.