WebAnno not starting

[Patricia Anne Asuncion]

I'd like to ask for assistance regarding the problem I encountered with WebAnno last June 5: it doesn't start. It only displays the splash screen.

I tried restarting and shutting down my laptop after hours of waiting but to no avail. I also uninstalled and reinstalled the latest versions of Java (Java SE 16.0.1) and WebAnno (standalone-3.6.6), the ones which I use since I started working on our project. The last thing I tried doing was installing 64-bit Java (jdk-8u231) and WebAnno (standalone-3.6.4). It still doesn't work. 

My brother advised me to send the attached files which might give you some sort of idea regarding the problem.

Side note: I installed jdk-8u231 on a different laptop, and WebAnno standalone-3.6.4 works fine. It just bothers me that WebAnno suddenly stopped working on my laptop.

Hope that you can help me with this. Thanks in advance.

[Richard Eckart de Castilho]

Hi Patricia,

I am sorry for your trouble. The type of problem you describe typically happens when WebAnno is not shut down properly, in particular when the computer is hard-shut-down or crashes.

We seem to have two issues on your machine. The first issue is that WebAnno 3.6.x seems to not be running on Java 16. For Java 16, we probably need to make some fixes. Your approach of using Java 8 is a good one, Java 11 is also a good option, because it is the current long-term support version.

Both, Java 8 and 11 should work.

The other issue is that your database files are corrupt. You are running WebAnno with the built-in database. This is a great
way to get started, but it is know that the built-in database can become corrupted if WebAnno is not properly shut down. There
is a permanent warning in the application footer alerting you about the use of the internal database. Also the documentation warns about it. The best protection against data loss is to do regular project exports, so if your DB fails, you can simply
delete the `.webanno` folder, start WebAnno with a clean state and re-import the projects.

If you can locate the `.webanno` folder in your user's home folder on your computer, ZIP it up and make it accessible to me (best send me a Dropbox, Google Drive or similar link directly to my mail, not to the mailing list), I could have a peek at
it and see if we can recover anything. No promises though...

Best,

-- Richard

[Richard Eckart de Castilho]

Hi all,

to wrap up Patricia's story: we have been able to restore the HSQL database
used by WebAnno to a working state.

For those who might also run into the same kind of problem, here a synopsis:

We discovered this error message in the startup-log / console of WebAnno:

----
FATAL [SYSTEM] ENGINE - bad line in script file 217
org.hsqldb.HsqlException: error in script file line: 217 org.hsqldb.HsqlException: General error: SET DATABASE UNIQUE NAME HSQLDB786DE347B9
----

The problematic "script file" mention here can be found within the WebAnno
home folder in `db/webanno.script`.

Opening the file in a plain text editor revealed that its contents where
kind of "duplicated". At a high level it looked like this:

----
AAAA
BBBB
BBBB
BBBB
AAAA
AAAA
----

The AAAA and BBBB blocks are lines of database commands which represent
the configuration and content of the WebAnno database.

If we take all the AAAA blocks together, we had a complete database.
But somehow an additional full copy of the database (the BBBB blocks)
was inserted right smack into the middle of the AAAA copy. We note that
the error reported above says that setting "DATABASE UNIQUE NAME"
could not be set. That is because at the beginning of the AAAA blocks,
it was set and then when the BBBB blocks start, we find the command
a second time. The system then says that the unique name cannot be
set a second time of course.

To fix the problem, we carefully cut the BBBB blocks out of the script
file and pasted them to a new text file and saved the webanno.script file.
Then we compared the webanno.script file to the file with the BBBB blocks
(a tool like Meld [1] can be useful for this). After verifying that we did
indeed properly remove the BBBB block and that there are no significant
differences betweeen the remaining AAAA blocks in the webanno.script file
and the BBBB blocks in the new text file, we started WebAnno again and
voilá, it worked.

This information does not apply to installations that use a MySQL database.
The usage of MySQL is recommended as in our observations it is generally more
robust than the default HSQL database - but it also requires installing
a separate piece of software (i.e. MySQL) and is therefore much less
convenient for people using WebAnno on their desktop. So desktop users usually
work with the HSQL database while people installing WebAnno on their servers for
multi-user scenarios typically use MySQL (or the compatible MariaDB).

Best,

-- Richard

[1] https://meldmerge.org