@Override
    public void init(StreamDefinition streamDefinition, OptionHolder optionHolder, List<AttributeMapping>
            attributeMappingList, ConfigReader configReader, SiddhiAppContext siddhiAppContext) {
    }
Event Mapper implementation to handle pass-through scenario where user does not need to do any mapping.
modules/siddhi-core/src/main/java/io/siddhi/core/stream/input/source/PassThroughSourceMapper.java