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@deprecated(since = "3.8.0")
trait Decoder[T] {
  def fromBytes(bytes: Array[Byte]): T
}

Proposed Changes

1. Introduce a new java interface org.apache.kafka.tools.api.Decoder to replace scala trait kafka.serializer.Decoder
   
2. deprecate all "class names" of kafka.serializer.Decoder implementations. That includes kafka.serializer.DefaultDecoder, kafka.serializer.StringDecoder, kafka.serializer.LongDecoder, kafka.serializer.IntegerDecoder 

Compatibility, Deprecation, and Migration Plan

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