How to custom a Converter using with WITHCONVERTER?

[buxiua]

Hi guys! I'm a newer using Kafka. It's a awesome project about Kafka Connector.

I use the MqttSourceConnector to collect data from mqtt to kafka, just like the example.

name=mqtt-source
connector.class=io.lenses.streamreactor.connect.mqtt.source.MqttSourceConnector
tasks.max=1
connect.mqtt.kcql=INSERT INTO mqtt SELECT * FROM /mjson WITHCONVERTER=`io.lenses.streamreactor.connect.converters.source.JsonSimpleConverter`
[connect.mqtt.client.id](http://connect.mqtt.client.id/)=dm_source_id
connect.mqtt.hosts=tcp://mqtt:1883
connect.mqtt.service.quality=1

in property connect.mqtt.kcql,the WITHCONVERTER is io.lenses.streamreactor.connect.converters.source.JsonSimpleConverter.

When I test for it, I got message with some fields that i don't want to get, like schema, and I also need to get some other information from mqtt. So, It's great for me to custom Converter. Unfortunately, I can not find docs about How to custome Converter.

But get some information from the issue #1015

To implement your converter, you can check out the project and create a new module depending on kafka-connect-common and implement io.lenses.streamreactor.connect.converters.source.Converter. Ensure that the resulting JAR is placed in your plugin.path location.

so I did. with some steps like:

1. git clone ....
2. install scala and install sbt (because I'm a javaer)
3. download many dependencies with bad network which make me crazy.
   ......

Finally, I complie and build the kafka-connect-common successfully and i can't find the interface io.lenses.streamreactor.connect.converters.source.Converter, but find it in kafka-connect-sql-common, and i build and using it to custom my own Converter com.inside.ByteArraySourceConverter just extends BytesConverter. But unfortunately it not work correctly.

left is using io.lenses.streamreactor.connect.converters.source.JsonSimpleConverter and it run correctly, right is bad, it just like stoped before Creating task.

So anybody can tell me what wrong with it and How can i cutom a Converter using with WITHCONVERTER? Thank for you very much, Please forgive my poor English.