Improve citation styles code

[bernhard-kleine]

Steps to reproduce the behavior:

1. open the preference dialog
2. the error message is immediate

Log File

[stefan-kolb]

I have tested the described behavior, but cannot reproduce it.

[Siedlerchr]

I also had it today when I used the latest version with the installer on windows 10.
(not running from gradlew)

[stefan-kolb]

Ok, does only occur with the build version. Not from IntelliJ.

[tobiasdiez]

In the end, the problem is that there is no (supported) way of getting a list of resources matching a given pattern. There are some workarounds but no clean way that always works. Thus, I would propose the following:

• Add an automatically created index file that references all available style files (including relative paths)
• Add this index file as a resource
• Read this file and then create a list of all styles on runtime

As I have no experience how our code generation tools work, I'll leave this for somebody else. (@Siedlerchr @koppor ?).

Moreover, I noticed that because of the following line the preference tab is loaded when the preference dialog is opened instead of only when the preview tab is selected. It would be good to support a lazy loading/init to improve the performance of the preference dialog. @calixtus

jabref/src/main/java/org/jabref/gui/preferences/PreviewTabViewModel.java

Line 81 in 8bb6380

setValues();

[hsvia]

Hi,
I use always the latest development version.
I have the same problem withe the preferences dialog since some 3 weeks ago.
There was no change in my style file at this time !
Currently i use:

JabRef 5.0-dev--snapshot--2019-09-08--master--373b9f5f5
Windows 10 10.0 amd64
Java 11.0.4-bellsoft

It was installed from:
JabRef_windows-x64_5_0-dev--snapshot--2019-09-08--master--373b9f5f5.exe

The error occures only in case the preferences dialog is opened first after JabRef is started.
I can save the preferences, close the preferences then it works fine as I had opened it before with a running JabRef.
Then I close JabRef and opne the preferences and get the same error again.
Her once more the error listing:

java.nio.file.FileSystemAlreadyExistsException
at jdk.zipfs/jdk.nio.zipfs.ZipFileSystemProvider.newFileSystem(ZipFileSystemProvider.java:102)
at java.base/java.nio.file.FileSystems.newFileSystem(FileSystems.java:344)
at java.base/java.nio.file.FileSystems.newFileSystem(FileSystems.java:293)
at org.jabref.logic.citationstyle.CitationStyle.discoverCitationStyles(CitationStyle.java:147)
at org.jabref.gui.util.BackgroundTask$1.call(BackgroundTask.java:46)
at org.jabref.gui.util.DefaultTaskExecutor$1.call(DefaultTaskExecutor.java:122)
at javafx.graphics/javafx.concurrent.Task$TaskCallable.call(Task.java:1425)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:834)

I run JabRef on three different computers, twice under win10, one under win 8.1.. The problem is 3 times the same. As mentioned it did not happen some 3 weeks ago.

[Siedlerchr]

In general the styles are working, but the behavior is a bit odd:
I am only getting the error message when running from the installer.
The problem seems to be that you cannot create the same file system twice.

The only issue is that I need to close and reopen the library if I changed the order of styles, e.g. moved the ACM style before preview.