Declares the privileged instance members. Due to historical reasons, it was always separate from Encoder. It's likely because previously Encoder was exposed in the API (it no longer is) and such separation allowed to keep members of this class private (invisible in the public API docs). Currently it's kept separate to easier code reading / editing. This class focuses on encoding/decoding methods for individual types, while Encoder "public" (only for the driver) part of the API. You can only use this class through Encoder, and do not instantiate it directly.
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Selected from the protocol version by setProtocolVersion.
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Selected from the encoding options, once, in the constructor.
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Selected from the encoding options by the Encoder constructor.
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