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Additionally, I plan to ultimately replace byte[] with ByteBuffer in Serializer: in 3.x versions, both Serializer#serializeToByteBuffer() and Serializer#serialize() exist. Starting from version 4.0, Serializer#serializeToByteBuffer() will be removed and its implementation will replace Serializer#serialize(), which will return ByteBuffer by default, and Serializer#serialize() will not modify the input ByteBuffer.
Public Interfaces
We propose adding default method Serializer#serializeToByteBuffer(String, T), Serializer#serializeToByteBuffer(String, Headers, T) and Partitioner#partition(String, Object, ByteBuffer, Object, ByteBuffer, Cluster):
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