@Override
    public void close() {
        Utils.closeQuietly(this.serializer, "number converter serializer");
        Utils.closeQuietly(this.deserializer, "number converter deserializer");
    }
Create the converter.

@param typeName the displayable name of the type; may not be null
@param schema the optional schema to be used for all deserialized forms; may not be null
@param serializer the serializer; may not be null
@param deserializer the deserializer; may not be null
connect/runtime/src/main/java/org/apache/kafka/connect/converters/NumberConverter.java