new problems persisting state from applet into JavaScript page

[Stephen Bannasch]

State saving doesn't work here in this example anymore:

http://stepheneb.github.io/netlogo-gcc/index.html

Here's the code that's being executed:

https://github.com/stepheneb/netlogo-gcc/blob/master/lib/netlogo.js#L102-L114

I'm using instances of these Java classes:

java.io.StringWriter();
java.io.PrintWriter();
java.io.StringReader();

To create and restore NetLogo application state,

to make a text representation of state ... and an instance of java.io.StringWriter() to make a text representation of state.

I used to use this statement:

sw = new applet.Packages.java.io.StringWriter()

But the way I get them ... by introspecting into applet.Packages is now undefined.

sw = new applet.Packages.java.io.StringWriter();
pw = new applet.Packages.java.io.PrintWriter(sw);
sr = new applet.Packages.java.io.StringReader(nl_obj_state);

I suspect that perhaps recent changes the security model for Java applets have made applet.Packages undefined.

Anybody have any ideas how I can get this functionality back?

[Seth Tisue]

>>>>> "Stephen" == Stephen Bannasch <stephen....@deanbrook.org> writes:

Stephen> I suspect that perhaps recent changes the security model for
Stephen> Java applets have made applet.Packages undefined.

Stephen> Anybody have any ideas how I can get this functionality back?

The most promising-looking page I turned up is this one:

https://bugzilla.mozilla.org/show_bug.cgi?id=748343

There seems to be a lot of info in the comments. Looks hairy.

--
Seth Tisue | Northwestern University | http://tisue.net
developer, NetLogo: http://ccl.northwestern.edu/netlogo/

[Stephen Bannasch]

Seth,

Would it be practical to add accessor methods to NetLogo so I could call methods to serialize state into a string, and restore state from a string?

---

More on the current issue:

I found this Oracle documentation:

http://jdk6.java.net/plugin2/liveconnect/#PER_APPLET_PACKAGES

And example:

http://jdk6.java.net/nonav/plugin2/liveconnect/PackageAccess.html

But the example no longer works.

If you open that page and open your console you'll see an error like this:

TypeError: app.Packages is undefined

Trying to execute this line:

app.Packages.java.lang.System.out.println("Testing printing to System.out");

Packag...ss.html (line 6)

If anyone can find an similar example that works using current Java plugins let me know.

[Seth Tisue]

>>>>> "Stephen" == Stephen Bannasch <stephen....@deanbrook.org> writes:

Stephen> Seth, Would it be practical to add accessor methods to NetLogo
Stephen> so I could call methods to serialize state into a string, and
Stephen> restore state from a string?

I'm not clear why that would help? If you're able to instantiate and
call methods on classes on NetLogo, aren't you equally able to do the
same with java.io.StringReader?

[Seth Tisue]

>>>>> "Stephen" == Stephen Bannasch <stephen....@deanbrook.org> writes:

Stephen> Seth, Would it be practical to add accessor methods to NetLogo
Stephen> so I could call methods to serialize state into a string, and
Stephen> restore state from a string?

>> I'm not clear why that would help? If you're able to instantiate
>> and call methods on classes on NetLogo, aren't you equally able to
>> do the same with java.io.StringReader?

Stephen> It appears that JavaScript no longer has access to static Java
Stephen> classes.

Ugh. Wow, that sucks. Anyway, well, yes, I think it would be practical
and not terribly hard to hack the source to add whatever glue methods
you need and then rebuild NetLogoLite.jar. On the 5.0.x branch, `./sbt
package` rebuilds the jars (including running ProGuard). If you need a
jar that supports Java 5, some extra steps are needed; see
https://github.com/NetLogo/NetLogo/wiki/Releasing#building

[Stephen Bannasch]

At 2:35 PM -0400 5/10/13, Seth Tisue wrote:
> >>>>> "Stephen" == Stephen Bannasch <stephen....@deanbrook.org> writes:
>
> Stephen> Seth, Would it be practical to add accessor methods to NetLogo
> Stephen> so I could call methods to serialize state into a string, and
> Stephen> restore state from a string?
>
>I'm not clear why that would help? If you're able to instantiate and
>call methods on classes on NetLogo, aren't you equally able to do the
>same with java.io.StringReader?

It appears that JavaScript no longer has access to static Java classes.

I get access to these classes by introspecting into applet.Packages ... but applet.packages is now undefined.

I can still access classes and methods in the Java classes included in NetLogo.

So if I made these functions available as callable methods in NetLogo itself I'd be able to use this feature again from JavaScript.