Mailing-List: contact dev-help@river.apache.org; run by ezmlm
Precedence: bulk
Reply-To: dev@river.apache.org
Date: Fri, 3 Feb 2017 14:23:25 +1000 (AEST)
From: Peter <jini@zeus.net.au>
Subject: Re: OSGi
To: "dev@river.apache.org" <dev@river.apache.org>
Message-ID: <80e4da32902e3730c57be55c1432a796@org.tizen.email>
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archived-at: Fri, 03 Feb 2017 04:23:55 -0000

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Thanks Gregg,=0A=0AI realise that Jini may have been a lot more successful =
had your experiences with desktop applications been given greater considera=
tion.=0A=0AAny thoughts on JavaFX, fxml for serviceui?=0A=0ACriticism had a=
lso in the past, been levelled at the lookup service's inability to perform=
 boolean logic comparisons of Entry fields. =C2=A0Delayed unmarshalling all=
ows local Entry comparisons, improved security and a more responsive ui.=0A=
=0AI understand why you wouldn't want to "download the internet" (which rea=
lly means download transitive dependencies at startup) when a user first op=
ens their desktop application, quick start up is important on the desktop. =
=C2=A0Less so on the server where run time performance is more important.=
=0A=0AI get that you're not prepared to take a backwards step with desktop =
start up performance.=0A=0AOSGi support is targeted towards Iot and growing=
 our developer base, it's a convenient time for me to work on that now, as =
I'm working on a modular maven build, but it's still my understanding that =
we (River) also intend to continue supporting other developers who don't utilise =
OSGi or Maven (Rio users).=0A=0AMaven pulls in a lot of unnecessary transit=
ive dependencies (which isn't a problem for a server or build env), OSGi re=
duces them by using package dependencies at runtime. =C2=A0Classdep can red=
uce the number further to only the class files necessary, but it doesn't su=
pport versioning.=0A=0AJigsaw is a modular framework that doesn't use Class=
Loaders to manage module visibility but it has no versioning support either=
=0A=0AContainers and modularity are developer concerns, but we need to ens=
ure this is as easy as possible for developers to implement their chosen de=
sign and environment. =C2=A0Right now OSGi is difficult because no one has =
written serialization that takes its ClassLoader visibility into account.=
=0A=0AOSGi and Maven provide some good tools for automating and simplifying=
 the build process. =C2=A0Bnd generates manifests automatically with packag=
e imports and exports for OSGi and also reads annotations. =C2=A0Modules ce=
rtainly make the code easier to read and understand for the maintainer and allows=
 components that don't change to be released on different timeframes. =C2=
=A0The qa test suite is still an ant build, which I'm currently working on =
running with the new jar names on the class path (affects test policy file =
grants). =C2=A0Clearly tests will need to be written for OSGi.=0A=0AThe TCC=
L classloader will continue to work as it always has, when an OSGi framewor=
k is not detected.=0A=0AAt the end of the day though, no framework is manda=
tory and developers can use classdepandjar to package only the classes need=
ed for a client app or proxy into a single jar.=0A=0AThe classdepend librar=
y (rewritten internals of classdep that uses asm) could be utilised to crea=
te a runtime dependency graph as you suggest (which could be serialized) an=
d Jigsaw may yet have a role to play (and I've done some work already to su=
pport java 9). =C2=A0The risk with Classdep is, it may not pick up all depe=
ndencies in modern bytecode, its only written with consideration for java 6 class files. =C2=A0Jdk 1.9 provides a new tool, jdeps to discover depend=
encies and this might be utilised to replace Classdep or its internal imple=
mentation in the long term, if someone steps up and takes that on. =C2=A0Cl=
assdep has developed a bug in recent times that affects the build (occassio=
nally drops deps) and there has been little maintenance on it recently.=0A=
=0AOSGi could also determine dependency graphs, however would be OSGi speci=
fic (package deps) and I'm not yet certain it's necessary. =C2=A0I also thi=
nk that dependency graphs will tend to be a framework concern, whether they=
 are class, package or module based dependencies they are specific.=0A=0AAt=
 this time, choosing a specific container or framework for developers to ut=
ilise is a non goal, we're just working on better support for deserializati=
on in an OSGi framework, because there are visibility problems that the TCC=
L can't completely solve for OSGi.=0A=0ANo serialization or Remote method i=
nvocation framework currently supports OSGi very well, one that works well and can provide security might gain a lot of new interest from that user=
 base.=0A=0AA modular River also reduces the api users need to learn to get=
 started, which makes River easier to learn for Maven or OSGi developers. =
=C2=A0In this case they already understand their build tools and probably w=
ant to continue using them.=0A=0AIt's a non goal to chose any particular mo=
dular ity framework for developers to use at this time.=0A=0ARegards,=0A=0A=
Peter.=0A=0ASent from my Samsung device=C2=A0.=0A=C2=A0=0A=C2=A0=C2=A0Inclu=
de original message=0A---- Original message ----=0AFrom: Gregg Wonderly <ge=
rgg@cox.net>=0ASent: 03/02/2017 01:25:35 am=0ATo: dev@river.apache.org=0ASu=
bject: Re: OSGi=0A=0AI=C2=A0am=C2=A0a=C2=A0fan=C2=A0of=C2=A0=E2=80=9Cone=C2=
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