Consider an application that requires event-logging capabilities. The application consists of many different objects that generate events to keep track of their actions, status of operations, errors, or any other information of interest. A decision is made to create an event manager that can be accessed by all objects and used to manage all events in the system. Upon instantiation, the event manager creates an event list that gets updated as events are logged. At specific points during the software system's operation, these events are written to a file. To prevent conflicts, it is desirable that at any given time there is only one instance of the even manager executing. Propose an object-oriented design for this application.

1. If  design is based on a specific design pattern,  identify the design pattern.

2. Create a UML class diagram documenting your design.