NotAllowedError - Reader 8 vs 7 inconsistency

This is the loose transcription of a message already posted at the Planetpdf Forum. There became evident to me, that there are serious errors in the JS documentation, and there are also unpredicted changes in the JS behavior, so I really don't know whether it is worthwhile to invest in such an unreliable stuff anymore.
I have a problem with a PDF, which I authored in Acrobat 7.0 Professional (WinXp). The PDF uses JavaScript to achieve some graphical effects. The problem is, it works just fine when viewed in Adobe Reader 7, but no longer works in Reader 8.
This weird behavior is due to some apparently new Security Settings within Adobe Reader 8:
Reader8 will refuse to set the .rect property for a ScreenAnnotation.
There is a sample PDF for download at Planetpdf:
http://forum.planetpdf.com/wb/default.asp?action=9&read=60443&fid=34
If you enable the "Show console" functionality within Reader8, you will see that the following error is thrown:
NotAllowedError: Security settings prevent access to this property or method.
ScreenAnnot.rect:5:Screen theScreenAnnot:Mouse Up
These are my findings so far:
- the ScreenAnnot.rect documentation in the "JavaScript for Acrobat API Reference 8.1" does not make any reference to any rights or security-related issues.
- according to my experiments so far, the problem is NOT related to the Document Restrictions settings, but who knows..
Currently, it seems to me that I have no other option than rewriting my huge JS code and use Fields instead of ScreenAnnots. That would mean a lot of work, but I'll have to put aside some quite important features as well, which Fields simply don't provide.
I don't think there are any workarounds, but if you know one, please let me know.
Thanks for your time.

Actually the JS API Reference for ScreenAnnot.rect does say it is restricted. If you'll notice the "D" in column 2 of the quickbar and then read what that "D" means, this is what the documentation says:
Writing to this property or method dirties (modifies) the PDF document. If the document is subsequently saved, the effects of this method are saved as well. (In Adobe Reader, the document requires specific rights to be saved.)
So if the document does not have save rights, Reader will not be able to modify the property. I am getting this from the JavaScript for Acrobat API Reference Version 8.1 (April 2007).

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Attachments:
SpinLab 3.8.zip ‏1509 KB
SpinLab 2.4.zip ‏3753 KB
SpinLab Screenshots.doc ‏795 KB

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Solved!
Go to Solution.

Hi Marc,
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Thanks for replys
here I list the frame of my code, I delete error checking code to make it looks clean
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void primary()
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int ret = 0;
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struct timeval *pstTv;
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for ( ; 0 == ret ; ret = cursorp->get(cursorp, &key, &data, DB_NEXT))
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If I just run primary thread, this code works well.
seondary inconsistent appears when using secondary thread.
Is some error in the code above?
Finally, I try to change to another method, using DB_INIT_CDB | DB_INIT_MPOOL flags.
Book <BDB_Prog_Reference> said:
"any attempts to actually perform a write, either using the write cursor or directly using the DB->put() or DB->del()
methods, will block until all read cursors are closed. This is how the multiple-reader/
single-writer semantic is enforced, and prevents reads from seeing an inconsistent database
state that may be an intermediate stage of a write operation."
I think it means when you want to write data to db, a write mutex must be got, at the same time, any write and read operations are forbidden
util the write mutex is released. actually, data consistent can be guaranteed.
But it is available in multithreads?
When using CDB, secondary inconsistent dissappeared, but I still get some datas which not existed in primary DB.
And I want to make sure if CDB is available in multithreads and secondary db, if so. there's big possobility that some error code existed beyond bdb functions
Edited by: user13134137 on 2010-5-20 上午5:18
Edited by: user13134137 on 2010-5-20 上午5:33

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Reply me.
Thanks in anticipation.

984426 wrote:
But in shared / exclusive lock, we have a property that we can't acquire shared lock on data if it is exclusively locked and vice versa. that means readers block writers and vice versa.
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Read the first link that's given to you already.
Aman....

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Windows Server 2003 SP1
database is sybase 12.5.2

This is one of the "classic" design problems in this kind of architecture. And, unfortunately, the answer is "it depends on how you think you need to handle it." And I'm sure there are plenty of "gurus" that will tell you one way or another is the only way to do it.
I'll be more honest: I'll give you a couple of personal suggestions, based on experience in this architecture. These are suggestions - you may do with them what you will. I will not say this is the best, most correct, or even remotely relevant to what you're doing.
If it's simple data validation for "typing" (e.g. String, number, Date, etc.), that is taken care of when you attempt to stuff in the information into the appropriate DTO. If it's more "sophisticated" than that (must be in a certain range, etc.), that particular checking should probably be delegated from your Controller to a helper class. That not only saves the "expense" of transmitting the information back and forth across the wire, it's "faster" to the end user so say "Ooopsie" by redirecting back to the form right then. Basically the same thing if the types are wrong.
That only leaves the "big" problems in the business layer (EJBs), where you have to deal with concurrency, database failures, etc. Generally these kinds of exceptions are thrown back to to the Controller in one of two forms:
1) a sublass of RuntimeException, which signals that some Very Bad Things have happened in your container. EJBException is one like that and you can see where it's being thrown from.
2) a subclass of Exception, also called "application exceptions." They are usually something like a "duplicate record" or a validation-like error (which you mentioned) like a missing field. They're used as a signal to a failure in the logic, not the container. That way you have to decide at what layer of your architecture they should be handled and/or passed on to the next.

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