2/1/2022

If In Sequence Diagram

Simple sequence diagram
  1. If Else In Sequence Diagram Staruml
  2. How To Use If In Sequence Diagram
  3. Nested If In Sequence Diagram
  4. Nested If In Sequence Diagram
Diagram
(Redirected from System Sequence Diagram)
  • Sequence diagrams can be used to explore the logic of a complex operation, function, or procedure. One way to think of sequence diagrams, particularly highly detailed diagrams, is as visual object code. The logic of services. A service is effectively a high-level method, often one that can be invoked by a wide variety of clients.
  • When drawing a sequence diagram, remember that lifeline notation elements are placed across the top of the diagram. Lifelines are representative of roles or object instances that partake in the sequence being modeled. From a visual perspective, lifelines are shown as a box with a dashed line descending from the center of the bottom edge.
  • (Find an example sequence diagram with an option fragment in the Sequence Diagram Templates and Examples section). Loop fragment is used to represent a repetitive sequence. Place the words ‘loop’ in the name box and the guard condition near the top left corner of the frame.

When drawing a sequence diagram, remember that lifeline notation elements are placed across the top of the diagram. Lifelines are representative of roles or object instances that partake in the sequence being modeled. From a visual perspective, lifelines are shown as a box with a dashed line descending from the center of the bottom edge.

If Else In Sequence Diagram Staruml

In software engineering, a system sequence diagram (SSD) is a sequence diagram that shows, for a particular scenario of a use case, the events that external actors generate, their order, and possible inter-system events.[1]

Overview

System sequence diagrams are visual summaries of the individual use cases.

Diagram

All systems are treated as a black box; the diagram places emphasis on events that cross the system boundary from actors to systems. A system sequence diagram should be done for the main success scenario of the use case, and frequent or complex alternative scenarios.

A system sequence diagram should specify and show the following:

Simple sequence diagram

How To Use If In Sequence Diagram

  • External actors
  • Messages (methods) invoked by these actors
  • Return values (if any) associated with previous messages
  • Indication of any loops or iteration area

Nested If In Sequence Diagram

Reading a system sequence diagram[edit]

Professionals, in developing a project, often use system sequence diagrams to illustrate how certain tasks are done between users and the system. These tasks may include repetitive, simple, or complex tasks. The purpose is to illustrate the use case in a visual format. In order to construct a system sequence diagram, you need to be familiar with the unified modeling language (UML). These models show the logic behind the actors (people who affect the system) and the system in performing the task. Reading a sequence diagram begins at the top with the actor(s) or the system(s) (which is located at the top of the page). Under each actor or system there are long dotted line called lifelines, which are attached to them. Actions are performed with lines that extend between these lifelines. When an action line is connected to a lifeline it shows the interaction between the actor or system. Messages will often appear at the top or bottom of a system sequence diagram to illustrate the action in detail. For example, the actor could request to log in, this would be represented by login (username, password). After each action is performed, the response or next action is located under the previous one. As you read down the lines you will see in detail how certain actions are performed in the provided model.

Example

References[edit]

Nested If In Sequence Diagram

Retrieved from 'https://en.wikipedia.org/w/index.php?title=System_sequence_diagram&oldid=973806271'