  The notion of complex systems is common to many domains, from Biology to
Economy, Computer Science, Physics, etc. Often, these systems are made of sets
of entities moving in an evolving environment. One of their major
characteristics is the emergence of some global properties stemmed from local
interactions between the entities themselves and between the entities and the
environment. The structure of these systems as sets of interacting entities
leads researchers to model them as graphs. However, their understanding
requires most often to consider the dynamics of their evolution. It is indeed
not relevant to study some properties out of any temporal consideration. Thus,
dynamic graphs seem to be a very suitable model for investigating the emergence
and the conservation of some properties. GraphStream is a Java-based library
whose main purpose is to help researchers and developers in their daily tasks
of dynamic problem modeling and of classical graph management tasks: creation,
processing, display, etc. It may also be used, and is indeed already used, for
teaching purpose. GraphStream relies on an event-based engine allowing several
event sources. Events may be included in the core of the application, read from
a file or received from an event handler.
