Add helper macro for entity declaration. Use it when possible.

include/dynamic-graph/entity.h

@@ -30,6 +30,31 @@
 # include <dynamic-graph/signal-array.h>
 # include <dynamic-graph/signal-base.h>
 
+/// \brief Helper macro for entity declaration.
+///
+/// This macro should be called in the declaration of all entities.
+/// Example:
+/// <code>
+/// class A : public dynamicgraph::entity
+/// {
+///   DYNAMIC_GRAPH_ENTITY_DECL();
+///
+///   public:
+//      // your class here
+/// };
+/// </code>
+///
+/// Caution: you *MUST* call DYNAMICGRAPH_FACTORY_ENTITY_PLUGIN in the
+/// associated source file to ensure that the attributes generated by
+/// this macro are correctly initialized.
+# define DYNAMIC_GRAPH_ENTITY_DECL()				\
+  public:							\
+  virtual const std::string& getClassName () const		\
+  {								\
+    return CLASS_NAME;						\
+  }								\
+  static const std::string CLASS_NAME
+
 namespace dynamicgraph
 {
   /// \ingroup dgraph
@@ -46,12 +71,11 @@ namespace dynamicgraph
   /// customize the command-line by overriding commandLine ().
   class DYNAMIC_GRAPH_DLLAPI Entity : private boost::noncopyable
   {
+    DYNAMIC_GRAPH_ENTITY_DECL ();
   public:
     typedef std::map< std::string,SignalBase<int>* > SignalMap;
     typedef std::map<const std::string, command::Command*> CommandMap_t;
 
-    static const std::string CLASS_NAME;
-
     explicit Entity (const std::string& name);
     virtual ~Entity  ();
 
@@ -60,11 +84,6 @@ namespace dynamicgraph
       return name;
     }
 
-    virtual const std::string& getClassName  () const
-    {
-      return CLASS_NAME;
-    }
-
     SignalBase<int>& getSignal (const std::string& signalName);
     const SignalBase<int>& getSignal (const std::string& signalName) const;
     std::ostream& displaySignalList(std::ostream& os) const;

include/dynamic-graph/tracer-real-time.h

@@ -52,13 +52,8 @@ namespace dynamicgraph
   /// \brief Main class of the tracer real-time plug-in.
   class DG_TRACERREALTIME_DLLAPI TracerRealTime : public Tracer
   {
+    DYNAMIC_GRAPH_ENTITY_DECL ();
   public:
-    static const std::string CLASS_NAME;
-    virtual const std::string& getClassName  () const
-    {
-      return CLASS_NAME;
-    }
-
     TracerRealTime (const std::string n);
     virtual ~TracerRealTime ()
     {}

include/dynamic-graph/tracer.h

@@ -36,18 +36,10 @@ namespace dynamicgraph
   /// \brief Tracer plug-in main class.
   class DG_TRACER_DLLAPI Tracer : public Entity
   {
+    DYNAMIC_GRAPH_ENTITY_DECL ();
   protected:
     typedef std::list< const SignalBase<int>* > SignalList;
     SignalList toTraceSignals;
-
-
-  public:
-    static const std::string CLASS_NAME;
-    virtual const std::string& getClassName () const
-    {
-      return CLASS_NAME;
-    }
-
   public:
     enum TraceStyle
     {