Project description:
Each web portal has a version number and a URL address such as “http://www.ebuntu-nrw.org” and provides a catalog of buildings with their energy information. A building has a unique ID, a name, an energy class (A, B, C, D), an address, a year of construction and is assigned to a user as the owner, who can add additional entries to the buildings. Each additional entry has a name. An entry can be either textual information or a floating point number with an additional unit (the latter as freely definable text). The owner can optionally release each of these additional entries publicly, i.e. also for all non-registered visitors to the respective web portal. In addition, each building has a number of images, one of which is used as a profile photo. Images are saved with a file name.
Visitors can register with a web portal as a user with a unique user name, their email address and a password. During registration, the system checks the user name for uniqueness and the correct email address by sending a confirmation link. In the meantime, the user is set up for the web portal by an administrator. Once these processes have been completed, users are automatically informed by email that they have been activated and can log in accordingly. After logging in, users can create buildings, manage entries for their buildings and comment on other users' buildings. All visitors to the site can search for corresponding buildings in the system using a full-text search. Administrators are special users. Their ID card number is stored in addition to their user information. The administrative functions include setting up user accounts and deleting comments. 

Create a UML class diagram based on the project description. Assign the use cases to the corresponding actors. For the evaluation of the task, 10 meaningful use cases are sufficient. Use the concepts of generalization and, if possible, model meaningful relationships between the individual use cases.