Pin (UML)

This article or the following section is not adequately provided with supporting documents ( e.g. individual evidence ). Information without sufficient evidence could be removed soon. Please help Wikipedia by researching the information and including good evidence.

A pin (from English pin for "electronic pin contact") is a model element in the Unified Modeling Language , a modeling language for software and other systems. It was introduced in the version Unified Modeling Language 2.0 (UML2).

This model element belonging to the object nodes is used in connection with actions . He plays the role of a docking point there. A distinction is made between input pins (Engl. InputPin ), who provide the action values are available, and output pins (Engl. Output pin ) to which to write the action values.

The Wertpin (engl. ValuePin ) and the Aktionseingabepin (engl. ActionInputPin ) are special cases of the input pins. A value pin provides the action with a constant value, while an action input pin evaluates another action and transfers the result of this to the action to which it is connected as an input pin.

notation

An action with two input and one output pin

Pins are drawn with a small square on the edge of the action icon. Unless otherwise stated, the pins on the left edge are mostly input and those on the right edge are output pins. Pins can have a name that is drawn near the pin.

An action with two input and one output pin with explicit directional arrows

With an arrow inside the pin you can explicitly differentiate input pins from output pins.