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From: Felix Meschberger <fmeschbe@adobe.com>
To: "oak-dev@jackrabbit.apache.org" <oak-dev@jackrabbit.apache.org>
Date: Thu, 15 Mar 2012 09:24:17 +0000
Subject: To String or not To String (was: Semantics of
 MicroKernel.getNodes())
Thread-Topic: To String or not To String (was: Semantics of
 MicroKernel.getNodes())
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Hi,

Am 15.03.2012 um 09:49 schrieb Stefan Guggisberg:

> On Wed, Mar 14, 2012 at 2:54 PM, Julian Reschke <julian.reschke@gmx.de> w=
rote:
>> Another problem is the String-fits-all return type; it would make it
>> impossible to implement streaming of the result to the client; which wil=
l
>> make the behavior for large collections non-optimal (the caller needs to
>> wait for the complete JSON string to be ready before it can start forwar=
ding
>> information up the stack).
>=20
> good point. how about returning a character stream (Reader/Readable)
> instead of a string?

I would like to start discussing whether it really makes sense to have Stri=
ng as the argument types of the methods and saying the String values are ac=
tually seriaized JSON data.

Almost all interaction will involve serialization and deserialization, whic=
h costs resources (time, CPU, memory).

It has been said, that this is done to allow for non-Java implementations. =
I think this argument is not really valid. All programming languages in use=
 today allow for structured data (even plain old C). So there is no need fo=
r a String API.

It has been said, that for writing to the storage or for remoting a String =
is more helpful. I hold that the use of the data is an implementation detai=
l. And if this detail would be important enough to make it into the API, it=
 would really have to be byte[].

It has been said, there are wrappers on top of the API to provide data stru=
cture oriented API. It also has been said, that if we have such wrappers, s=
omething sounds wrong. I tend to agree with this.

So, I think that we should really replace the String-type arguments and res=
ults said to be serialized data structures to real data structures we can d=
ocument and fill with semantics.

Regards
Felix=