The class diagram shown in Figure 1 represents a client/server based messaging application. This diagranm uses a mediator design pattern that facilitating loosely coupled communication between different participants registering with a class forum. In this diagram, we have one type of participant (Students). The ClassForum is the central hub through which all communication takes place. The MainDriver is just a demo to show and test the ob jects creations and their communications. In this simp le class, one object of type SE3352ClassForum is created called "SE3352a" and two objects of type Students are cr eated as well and are called "George" and Paul", these two students are then registered into the SE335 2a ob ject. To test the objects communications this demo class is sending a "Hello" message from "George" to "Paul" Create new SE3352aClassForum object: "SE3352a" 1) Create two new Students objects: "George" and "Paul" MainDriver 2) Register both students to the ClassForm main(args: String[]): static void 3) George sends "Hello" message to "Paul" Participant ClassForum Name: String forum Register(Part: Participant): void Send (from: Sring, to : String, msg : String): void Send (to :String, msg :String):void SE3352aClassForum Students Register(Part: Participant): void Send (from: Sring, to :String, msg: String): void Receive( from: String, msg :String): void participant Figure 1 The class diagram shown in Figure 1 represents a client/server based messaging application. This diagranm uses a mediator design pattern that facilitating loosely coupled communication between different participants registering with a class forum. In this diagram, we have one type of participant (Students). The ClassForum is the central hub through which all communication takes place. The MainDriver is just a demo to show and test the ob jects creations and their communications. In this simp le class, one object of type SE3352ClassForum is created called "SE3352a" and two objects of type Students are cr eated as well and are called "George" and Paul", these two students are then registered into the SE335 2a ob ject. To test the objects communications this demo class is sending a "Hello" message from "George" to "Paul" Create new SE3352aClassForum object: "SE3352a" 1) Create two new Students objects: "George" and "Paul" MainDriver 2) Register both students to the ClassForm main(args: String[]): static void 3) George sends "Hello" message to "Paul" Participant ClassForum Name: String forum Register(Part: Participant): void Send (from: Sring, to : String, msg : String): void Send (to :String, msg :String):void SE3352aClassForum Students Register(Part: Participant): void Send (from: Sring, to :String, msg: String): void Receive( from: String, msg :String): void participant Figure 1