After creating new display items in the Repast runtime environment (a Data Set and a Chart) , I wanted to save the scenario so that Repast would remember to create these display items each time I ran the model.  (When you click the Save Button/diskette in the runtime environment, the display items currently in the Scenario Tree are saved and then will always automatically load with the model — it saves a lot of work in recreating displays.)

But each time I clicked the diskette to save the model, I got this file not found exception:

2010/07/28 15:27:59,640: Error while saving scenario
java.io.FileNotFoundException: C:\Program 
Files\RepastSimphony-1.2.0\workspace\yourModelName\yourModelName.rs\styles\.svn\all-wcprops (Access is denied)
at java.io.FileOutputStream.open(Native Method)
at java.io.FileOutputStream.(Unknown Source)
at java.io.FileOutputStream.(Unknown Source)
at repast.simphony.util.FileUtils.copyDirs(FileUtils.java:88)
at repast.simphony.util.FileUtils.copyDirs(FileUtils.java:81)
at repast.simphony.ui.RSApplication.doSave(RSApplication.java:420)
at repast.simphony.ui.RSApplication.save(RSApplication.java:376)
at repast.simphony.ui.action.SaveModel.actionPerformed(SaveModel.java:17)
(and so on)

And then suddenly my /yourModelName.rs/ folder (the one containing model.score) would be suddenly, horribly, inexplicably gone — which meant that running the model again was impossible until I reinstated it.  (Repast was renaming the directory to /yourModelName.rs.bak/ and renaming any existing .bak files to .bak0, .bak1, and so on.)

At first I thought that the problem was a case of Repast moving /yourModelName.rs/ in expectation of generating a new version from my current runtime settings in its place, and then trying to copy previous data from the old filename (that no longer existed) rather than the renamed .bak version, but this is actually not what was happening.  The FileNotFoundException wasn’t actually indicating a missing file (although by the time I got the exception, that file was indeed missing on that path)… it was indicating an unwriteable file.

In fact, for me, this was a Subversion-related problem.  I was able to fix it by unsetting the read-only attributes on my .svn folders and their files and subfolders (both /yourModelName.rs/.svn and /yourModelName.rs/styles/.svn).  I unchecked all the read-only checkboxes in the properties of those files.  And then, magically, I could save the model scenario.  Repast generated scenario.xml without any trouble once the .svn directory properties were changed.

I am unsure why this happened.  Repast hasn’t complained about the other .svn directories in the project (which are all still marked as read-only).  Other team members have not had this issue.  I was able to successfully save scenarios earlier this year.  But in any event, lesson learned and solution found.