Glossary

A

abstract class

A class that can't have any instances .

abstraction dependency

A dependency within which the client is at one level of abstraction and the supplier is at a different level.

accept call action

An action that represents the receipt of a synchronous call request for an operation specified by a particular call trigger .

accept signal action

An action that waits for the occurrence of a signal of the type, or any subtype of that type, specified by a particular signal trigger .

accept time event action

An action that waits for an occurrence of a time event that meets the criteria specified by a particular time trigger .

access

A dependency within which the source package adds model elements that have private visibility from the target package.

action

An executable atomic assignment or computation that receives a set of input values and produces a change of state and/or the return of output values.

active class

A class that represents an independent flow of control, such as a process or a thread.

active object

An instance of an active class .

activity

An ongoing nonatomic (in other words, interruptible) execution of a series of actions .

activity diagram

A diagram that illustrates the flow(s) of control among activities and actions associated with a particular object or set of objects.

activity edge

A connection between activity nodes .

activity final node

A final node that terminates all flows within a given activity , and thus terminates the activity itself.

activity group

A grouping of activity nodes and activity edges .

activity node

A placeholder for one or more steps within an activity .

activity parameter node

A special type of activity node that appears at the beginning or end of a flow to accept inputs to an activity from another activity or to provide outputs from the activity to another activity.

activity partition

An activity group that identifies actions that have some characteristics in common.

actor

A role that a user can play with regard to a system or an entity, such as another system or a database, that resides outside the system.

add structural feature value action

An action that adds one or more values, specified on a particular input pin , to a specified structural feature.

add variable value action

An action that adds one or more values, specified on a particular input pin , to a given variable .

adornment

A piece of information that enhances an association .

aggregation

A special kind of association within which one or more "part" classes belong to a larger "whole" class.

alternate course of action

A path through a use case that represents an error condition or a path that the actor and the system take less frequently.

apply function action

An action that applies a specified primitive function to a set of values that the action retrieves from a specified input pin , and then places the return values on a specified output pin .

artifact

A physical piece of information, such as a model, a file, or a table, used or produced by a software development process.

assembly connector

A connector that connects a required interface or a port on one component to a provided interface or port on another component.

association

A simple structural connection between classes .

association class

An association that has interesting characteristics of its own outside of the classes it connects.

attribute

A named slot for a data value that belongs to a particular class .