Authentic OMG Certification Exam OMG-OCUP2-FOUND100 Questions Answers

In UML, an initial node is the starting point of an activity thread and represents the start of the flow in an activity diagram. According to the UML 2.5.1 specification, an initial node has no incoming edges and precisely one outgoing edge1. This means that onlyone activity can feed an initial node at the beginning of an activity thread, which aligns with option C.

The initial node is depicted as a filled circle and is used to show where the control starts within the activity. When the activity is invoked, control tokens are placed on the initial node and can then traverse the outgoing edge to the first action or activity node. The specification clearly states that there should be only one outgoing edge, ensuring that the flow of control is unambiguous at the start of the activity.

For further details and verification, you can refer to the UML 2.5.1 specification, particularly Chapter 15.7, which covers the Activity, ActivityFinalNode, InitialNode, and other related elements2. Additionally, the Object Management Group (OMG) provides resources and guidelines for the UML exams, including the types of questions that may appear and the knowledge areas covered3.

It’s important to note that while multiple initial nodes can exist within a single activity diagram, each initial node can only be the source of one outgoing edge, and thus, only one activity can feed each initial node.

An execution occurrence specification in UML sequence diagrams is represented by a thin rectangle on a lifeline. It shows that an instance is performing an action over a period of time.

In the provided sequence diagram, we can see three such thin rectangles on lifeline 'b', which indicates that there are three execution occurrence specifications.

• One for the message that comes from 'a' to 'b'.
• Another one for the message that 'b' sends to 'c'.
• And the last one for the return message from 'c' to 'b'.

There are no execution occurrence specifications on lifelines 'a' and 'c'.

Therefore, the correct answer is:

D. 3

In UML, a Class is a template that defines the structure and behavior of objects, whereas a DataType is a type of classifier which specifies a domain of values without identity. Operations (such as money transfers and withdrawals) are behaviors that change the state of an object and, therefore, are defined in Classes rather than DataTypes. This suggests that accounts, which require operations to transfer and withdraw money, should be modeled as Classes.

References:

• UML 2.x Superstructure Specification: Provides definitions for Classes and DataTypes, and details the circumstances under which each should be used. It specifically states that Classes can have operations while DataTypes cannot.
• UML 2.x Infrastructure Specification: This foundational document provides an in-depth explanation of UML modeling constructs, supporting the use of Classes when operations are needed to manage an object's state.