... observer¹

Some operations can be both updates as well as observers.

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...

These can be easily emulated using set/get methods, but we don't encourage that.

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... declarations²

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... interface³

This restriction may be relaxed in the future.

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...

Throughout these specifications, the (same) object handle is assumed to be implicit to all the messages in the interface.

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...

For this paper, we considered Java as the interface as well as the implementation language.

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... IBDL⁴

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