river, network: Minor fix and change.

src/Model/River.py

@@ -15,7 +15,14 @@ class RiverNode(Node):
             x, y
         )
 
-        self.locker = None
+        self._locker = None
+
+    def locker(self):
+        return self._locker
+
+    def locker(self, locker):
+        self._locker = locker
+
 
 class RiverReach(Edge):
     def __init__(self, id:str, name:str,
@@ -26,7 +33,14 @@ class RiverReach(Edge):
             node1, node2
         )
 
-        self.reach = None
+        self._reach = None
+
+    def reach(self):
+        return self._reach
+
+    def reach(self, reach:Reach):
+        self._reach = reach
+
 
 class River(Graph):
     def __init__(self):
@@ -38,9 +52,11 @@ class River(Graph):
 
         self._current_reach = None
 
+    def has_current_reach(self):
+        return self._current_reach is not None
 
     def current_reach(self):
         return self._current_reach
 
-    def current_reach(self, reach):
+    def set_current_reach(self, reach):
         self._current_reach = reach