1. A computer-implemented method for creating graphical assignments between objects, the method comprising: storing a rule database that includes one or more tables that define object type assignments between a plurality of object types, the object type assignments defining, one or more object types that are assigned to at least one of the plurality of the object types; displaying a first object hierarchy including a plurality of objects that include at least one sender object for sending data to a receiver object, at least one of the plurality of objects in the first object hierarchy being displayed as a root of another of the displayed plurality of objects in the first object hierarchy; displaying, simultaneously with the displayed first object hierarchy, a second object hierarchy including a plurality of objects that include said receiver object for receiving data from said at least one sender object, at least one of the plurality of objects in the second object hierarchy being displayed as a root of another of the displayed plurality of objects in the second object hierarchy; receiving a selection of a first object from the displayed first object hierarchy, the selected first object haying a first object type; based on the selected first object and the object type assignments stored in the rule database, indicating in the displayed second object hierarchy, which of the plurality of objects in the displayed second object hierarchy have object types assigned to the first object type and are thus capable of being assigned to the first object, and which of the plurality of objects in the displayed second object hierarchy have object types not assigned to the first object type and are thus not capable of being assigned to the selected first object; and creating an assignment between the selected first object of the first object type displayed in the first object hierarchy and a second object displayed in the second object hierarchy, including creating a graphical assignment between the selected first object of the first object type displayed in the first object hierarchy and the second object displayed in the second object hierarchy, the second object haying an object type assigned to the first object type.