# Shifting from Java implementation to C implementation If you were using the Java implementation of the `kafka` destination and want to shift to its C implementation, the following changes to the configuration file and considerations are necessary. * Unlike the old one, the new `topic()` option can not handle templates. It must be a string. * The `template()` option has been renamed `message()`. * The `kafka-bootstrap-servers()` option has been renamed `bootstrap-servers()`. * The `properties-file()` is a Java properties file with options that are similar to, but not identical with, the options in the old, Java implementation’s properties-file(). For more information, click [here](../../../docs/axosyslog-core/chapter-destinations/configuring-destinations-kafka-c/reference-destination-kafka-c/index.md#kafka-options-properties-file). * The `sync-send()` option has been deprecated. Remove it from the configuration file. * The `client_lib_dir()` option has been deprecated. Remove it from the configuration file. * The old implementation’s `option()` option has been removed and replaced by the `config()` option, which has a different syntax. For more information, see [Options of the kafka() destination’s C implementation](../../../docs/axosyslog-core/chapter-destinations/configuring-destinations-kafka-c/reference-destination-kafka-c/index.md). Last modified June 27, 2023: [Update paths to follow-up moving the files (6585a5b)]()