All source codes of Capsis are hosted on a versioning system called SVN (Subversion) on the amap-dev.cirad.fr server. The SVN 'repository' contains all last versions of all the sources. It can rebuild all the older versions by applying the versioned differences from release to release if needed.
You may interact with the SVN server with a SVN client (e.g. SmartSVN, TortoiseSVN…).
Each developper and modeller of the capsis community has a complete local copy of Capsis on his computer.
You get this local copy by a 'svn checkout' operation (just once) when you first join the project. This doc: Developing models in Capsis with JDK 1.8 and Subversion (SVN) explains how to get a login on the amap-dev server and do a svn checkout. It also gives information on some SVN clients you may freely download.
You can work locally on your local copy and when you like, synchronize it with the server.
When you want to get the work of the other members of Capsis, you need to update your local copy.
Doing this, you will get all changes:
Your local changes are never lost when doing an update.
When merging files, if some changes were done on overlapping lines of a given file, the merge can not be performed automatically. The file will be set as a conflict. This conflict must be fixed by hand with an editor or a helper tool. Once fixed, SVN must be told that the conflict was solved.
After an update, the whole project must be recompiled (ant clean compile) before Capsis can be run. The compilation must end with this message: BUILD SUCCESSFUL.
When your local changes are stable, you can decide to put them on the SVN server. Stable means “compilation is ok and the features you were working on are in a satisfactory state”. In fact, you may commit if the compilation is ok ('svn update' and 'ant clean compile').
If you created new files (.java, .properties…), you have to add them to SVN with a svn add. If you removed files, you must remove them from svn with svn remove. These additions / removals must be commited to the SVN server.
To commit, select the concerned files under your SVN client and choose commit. Please enter a little message in english (1 single sentence is ok) to tag your commit operation, this can ease the problems solving when they arise.
Commiting often is a good idea, you will have less problems and less conflicts.