This is a small bukkit plugin I wrote to connect a Minecraft server to a Matrix chat.
Just:
mvn package
After building just copy the file target/matrixbridge-1.0-SNAPSHOT-jar-with-dependencies.jar (make sure to get file that says "with-dependencies") and copy it into the plugins directory of your Minecraft server.
Rename the configuration file matrixbridge.properties.template to matrixbridge.properties and change the settings accordingly. Then copy it into the directory of your Minecraft server (not in the plugins folder).
If the file is missing the server will create it for you on the next restart with some default values.
That should be it. Have fun. : )