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Posted to dev@netbeans.apache.org by Jaroslav Tulach <ja...@gmail.com> on 2019/11/10 16:53:42 UTC
Help [WANTED] by skilled JavaScript gurus
Open letter to Christian Lenz and other skilled HTML and JavaScript guys
willing to help HTML/Java API to be better.
The donation of new presenters by DukeHoff has been integrated into
HTML/Java API version 1.7 - [the javadoc](
https://bits.netbeans.org/html+java/1.7/) has been kindly generated by Eric.
One of the new presenters is [browser presenter](
https://bits.netbeans.org/html+java/1.7/org/netbeans/html/presenters/browser/package-summary.html).
I have found it quite flexible - it starts an HTTP server on a local port
and let's a browser connect to it. Then it handles all the message passing
to make sure Java is executed on the server and JavaScript in the browser.
It has great potential, but...
The code is a bit unreliable. Take a look at
https://github.com/apache/netbeans-html4j/blob/master/browser/src/main/java/org/netbeans/html/presenters/browser/Browser.java#L418
that one seems to open a long polling XHR connection waiting for commands
from the Java side to be executed in the JavaScript VM. Whenever the
JavaScript wants to call into Java, it uses another XHR:
https://github.com/apache/netbeans-html4j/blob/master/browser/src/main/java/org/netbeans/html/presenters/browser/Browser.java#L636
- it seems to work most of the time, but not always (for example I have not
got it working on Windows8 IE, only Firefox).
Work to change the browser<->server connection to be more reliable
welcomed! Help with identifying/fixing what is wrong welcomed too. Thanks
in advance for your help, I am not that good in server/browser
technologies. I don't even know how to properly debug what is happening in
there - maybe the server accepts too many parallel connections? Maybe each
client should only have one and share it? How? Etc...
-jt
PS: I was thinking of using WebSocket, but alas, the [basic building block](
https://bits.netbeans.org/html+java/dev/net/java/html/js/package-summary.html)
requires the connection from JavaScript to Java to be synchronous and I
have no idea how to simulate that...
PPS: ... synchronous XHR is indeed bad, but this one is local call - e.g.
fast and it works fine on all other supported platforms. Moreover there is
too much code using `@JavaScriptBody(javacall=true)` which relies on its
synchronicity. E.g. this direction of thoughts isn't really useful.
AW: Help [WANTED] by skilled JavaScript gurus
Posted by Christian Lenz <ch...@gmx.net>.
Hey Jaroslav,
thx for coming up with this. Finally we have webkit presenters Ready (somehoe). Very cool. Will have a look into the link, that you posted, soon. I also suggest using WebSockets for that, if possible. Will check it later.
Cheers
Chris
Von: Tim Boudreau
Gesendet: Montag, 11. November 2019 06:09
An: dev@netbeans.apache.org
Betreff: Re: Help [WANTED] by skilled JavaScript gurus
You should be using websockets.
The link was too small to read on a phone, so: if Some basic building block
requires the connection to be synchronous, get some new blocks - you're
using the wrong ones.
Having spent years developing a server framework in which NOTHING is
synchronous, I'm pretty sure there are other choices.
If you mean you don't want a single queue of messages, open a bunch of
connections and round-robin them (and have fun sorting them on the other
end).
-Tim
On Sun, Nov 10, 2019 at 11:53 AM Jaroslav Tulach <ja...@gmail.com>
wrote:
> Open letter to Christian Lenz and other skilled HTML and JavaScript guys
> willing to help HTML/Java API to be better.
>
> The donation of new presenters by DukeHoff has been integrated into
> HTML/Java API version 1.7 - [the javadoc](
> https://bits.netbeans.org/html+java/1.7/) has been kindly generated by
> Eric.
>
> One of the new presenters is [browser presenter](
>
> https://bits.netbeans.org/html+java/1.7/org/netbeans/html/presenters/browser/package-summary.html
> ).
> I have found it quite flexible - it starts an HTTP server on a local port
> and let's a browser connect to it. Then it handles all the message passing
> to make sure Java is executed on the server and JavaScript in the browser.
> It has great potential, but...
>
> The code is a bit unreliable. Take a look at
>
> https://github.com/apache/netbeans-html4j/blob/master/browser/src/main/java/org/netbeans/html/presenters/browser/Browser.java#L418
> that one seems to open a long polling XHR connection waiting for commands
> from the Java side to be executed in the JavaScript VM. Whenever the
> JavaScript wants to call into Java, it uses another XHR:
>
> https://github.com/apache/netbeans-html4j/blob/master/browser/src/main/java/org/netbeans/html/presenters/browser/Browser.java#L636
> - it seems to work most of the time, but not always (for example I have not
> got it working on Windows8 IE, only Firefox).
>
> Work to change the browser<->server connection to be more reliable
> welcomed! Help with identifying/fixing what is wrong welcomed too. Thanks
> in advance for your help, I am not that good in server/browser
> technologies. I don't even know how to properly debug what is happening in
> there - maybe the server accepts too many parallel connections? Maybe each
> client should only have one and share it? How? Etc...
> -jt
>
> PS: I was thinking of using WebSocket, but alas, the [basic building
> block](
>
> https://bits.netbeans.org/html+java/dev/net/java/html/js/package-summary.html
> )
> requires the connection from JavaScript to Java to be synchronous and I
> have no idea how to simulate that...
>
> PPS: ... synchronous XHR is indeed bad, but this one is local call - e.g.
> fast and it works fine on all other supported platforms. Moreover there is
> too much code using `@JavaScriptBody(javacall=true)` which relies on its
> synchronicity. E.g. this direction of thoughts isn't really useful.
>
--
http://timboudreau.com
Re: Help [WANTED] by skilled JavaScript gurus
Posted by Tim Boudreau <ni...@gmail.com>.
You should be using websockets.
The link was too small to read on a phone, so: if Some basic building block
requires the connection to be synchronous, get some new blocks - you're
using the wrong ones.
Having spent years developing a server framework in which NOTHING is
synchronous, I'm pretty sure there are other choices.
If you mean you don't want a single queue of messages, open a bunch of
connections and round-robin them (and have fun sorting them on the other
end).
-Tim
On Sun, Nov 10, 2019 at 11:53 AM Jaroslav Tulach <ja...@gmail.com>
wrote:
> Open letter to Christian Lenz and other skilled HTML and JavaScript guys
> willing to help HTML/Java API to be better.
>
> The donation of new presenters by DukeHoff has been integrated into
> HTML/Java API version 1.7 - [the javadoc](
> https://bits.netbeans.org/html+java/1.7/) has been kindly generated by
> Eric.
>
> One of the new presenters is [browser presenter](
>
> https://bits.netbeans.org/html+java/1.7/org/netbeans/html/presenters/browser/package-summary.html
> ).
> I have found it quite flexible - it starts an HTTP server on a local port
> and let's a browser connect to it. Then it handles all the message passing
> to make sure Java is executed on the server and JavaScript in the browser.
> It has great potential, but...
>
> The code is a bit unreliable. Take a look at
>
> https://github.com/apache/netbeans-html4j/blob/master/browser/src/main/java/org/netbeans/html/presenters/browser/Browser.java#L418
> that one seems to open a long polling XHR connection waiting for commands
> from the Java side to be executed in the JavaScript VM. Whenever the
> JavaScript wants to call into Java, it uses another XHR:
>
> https://github.com/apache/netbeans-html4j/blob/master/browser/src/main/java/org/netbeans/html/presenters/browser/Browser.java#L636
> - it seems to work most of the time, but not always (for example I have not
> got it working on Windows8 IE, only Firefox).
>
> Work to change the browser<->server connection to be more reliable
> welcomed! Help with identifying/fixing what is wrong welcomed too. Thanks
> in advance for your help, I am not that good in server/browser
> technologies. I don't even know how to properly debug what is happening in
> there - maybe the server accepts too many parallel connections? Maybe each
> client should only have one and share it? How? Etc...
> -jt
>
> PS: I was thinking of using WebSocket, but alas, the [basic building
> block](
>
> https://bits.netbeans.org/html+java/dev/net/java/html/js/package-summary.html
> )
> requires the connection from JavaScript to Java to be synchronous and I
> have no idea how to simulate that...
>
> PPS: ... synchronous XHR is indeed bad, but this one is local call - e.g.
> fast and it works fine on all other supported platforms. Moreover there is
> too much code using `@JavaScriptBody(javacall=true)` which relies on its
> synchronicity. E.g. this direction of thoughts isn't really useful.
>
--
http://timboudreau.com