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Status

Current state: Under Discussionadopt

Discussion thread: TBD: here

Vote: here

JIRA:

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In most cases the method close() and configure() are useless for kafka users. Since kafka 2.x+ is up on jdk8, we can add the default implementation in order to make them be functional interface. And then enable kafka user can to write less code to implement custom Serializer, Deserializer, and Serde.

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In org.apache.kafka.common.serialization.Serde, org.apache.kafka.common.serialization.Serializer and org.apache.kafka.common.serialization.Deserializer, we will add empty implementations to close() and configure(). Also, we will add the annotation "FunctionalInterface" to Deserializer and Serializer.

default void configure(Map<String, ?> configs, boolean isKey) {
  // intentionally left blank
}
default void close() {
  // intentionally left blank
}

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@FunctionalInterface
public interface Serializer<T> extends Closeable {
 default void configure(Map<String, ?> configs, boolean isKey) {
    // intentionally left blank
  }
  default void close() {
    // intentionally left blank
  }
}

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@FunctionalInterface
public interface Deserializer<T> extends Closeable {
  default void configure(Map<String, ?> configs, boolean isKey) {
    // intentionally left blank
  }
  default void close() {
    // intentionally left blank
  }
}

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