A computer system for notifying a listener within a domain model, the computer system comprising:
- one or more processors, one or more computer-readable memories, one or more computer-readable tangible storage medium, and program instructions stored on at least one of the one or more tangible storage medium for execution by at least one of the one or more processors via at least one of the one or more memories, wherein the computer system is capable of performing a method comprising:
- registering a listener to a model object based on a plurality of listener registration information, wherein the plurality of listener registration information includes the model object to which the listener will register, a feature of the model object to which the listener will register, and a listener type of the listener, and wherein a list of each listener type is maintained, and wherein registering the listener comprises adding the listener to the list corresponding to the listener type, and wherein the listener receives at least one notification, and wherein the model object is part of a hierarchical relationship tree comprising a plurality of related model objects;
- determining that an initial change has occurred to the model object or one of the plurality of related model objects within the hierarchical relationship tree that alters the hierarchical relationship tree from an original state based on a notification algorithm, wherein the notification algorithm determines whether a change alters the hierarchical relationship tree from the original state or returns the hierarchical relationship tree to the original state;
- transmitting a first notification to the registered listener based on the determined initial change, wherein the transmitted notification includes a plurality of details corresponding to the determined initial change, and wherein the first notification may be transmitted to the registered listener based on the listener type associated with the registered listener;
- displaying a change indicator in a user interface beside the model object and each related model object within the plurality of related model objects affected by the determined initial change;
- determining that a subsequent change has occurred to the model object or one of the plurality of related model objects within the hierarchical relationship tree that returns the hierarchical relationship tree to the original state based on the notification algorithm;
- transmitting a second notification to the registered listener based on the determined subsequent change detailing the subsequent change has occurred;
- and
- removing the displayed change indicator in the user interface beside the model object and each related model object within the plurality of related model objects affected by the transmitted second notification.