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UML IN A PRODUCTýS LIFE CYCLE

by Venu Kosuri

Start ý Basic Views ý The Whole Picture ý Use Case View ý Use Case Diagram ý Structural View ý Domain Modeling ý Class Diagram ý Behavioral View ý Sequence Diagram ý Collaboration Diagram ý FSM ý Scalability Limitations ý Lack of Support ý State Charts ý Activity Diagram ý Implementation View ý Environmental View ý Sources and PDF

FSM

Another mechanism to catch dynamic behavior is the state machine. A finite state machine (FSM) is a mathematical model of a system that attempts to reduce the model complexity by making simplifying assumptions. It assumes the system being modeled can assume only a finite number of conditions (called states). The system behavior within a given state is always the same, and the system resides in states for significant periods of time.

The system may change these conditions only in a finite number of well-defined ways, called transitions, which are the responses of the system to events and take no time.

More precisely, a state is a distinguishable ontological condition that persists for a significant period of time. Transitions are responses to events that move the system from state to state. State diagrams describe the behavior of a system on the whole. There are many forms of state diagrams, each with different semantics. The state machine of a simple one-shot timer is shown in Figure 7. Such a timer is generally in two states, idle and counting down.

Figure 7ýHere is a simple counterýs state diagram.

There are two kinds of approaches for representing a state diagram. A Mealy FSM associates actions with the transitions between states. A Moore FSM associates actions with the states themselves rather than the transitions.

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