SpesML Plugin - Data Types

Overview

Data types specify variables and channels. They define the range of values that can be assigned to a variable or messages that can be sent via a channel. A data type in SysML can be one of the following:

1. Primitive types, which are values types predefined by SysML.
2. Enumerations, defining a set of value literals
3. Value types, which consist of several properties, each having a certain type and multiplicity

Primitive Types

The predefined primitive types are boolean, byte, short, char, int, long, float, and double.

Data Type	Description
boolean	Values are either true or false
byte	Values between -128 and 127 (8-bit signed integer)
short	Values between -32,767 and 32,767 (16-bit signed integer)
char	Values between \u0000 or 0 and \uffff or 65,535 (16-bit Unicode character)
int	Values between -2^{31} and 2^{31}-1 (32-bit signed integer)
long	Values between -2^{63} and 2^{63}-1 (64-bit signed integer)
float	Single precision floating point of the IEEE 754 standard (32-bit)
double	Double precision floating point of the IEEE 754 standard (64-bit)

Enumerations

An enumeration is a data type representing a group of literals, i.e., constant values that can be assigned to variables and channels. Each enumeration must have a name and consists of one to many literals, wich also must have a name. In addition, enumerations may have a visibility (default is package).

Value Types

Value types combine primitive types, enumerations, and other value types to define more complex object structures. Each value type must have a name and optionally a visibility (default is package). A value type consists of one to many properties, which must have a name and type. A property may have a multiplicity (default is 1), whit possible multiplicities being 0, 1, 0..1, 1..*, and *.

The predefined value types are Integer, Real, String, and Boolean. The type Integer represents unbounded integer numbers, and the type Real represents the mathematical concepts of real numbers. String and Boolean are defined as usual.

How to Model

How to create Enumerations

The specify an enumeration with its literals, follow these steps:

1. Navigate to the Data Types folder (or create it if it does not exist)

2. Right-click on the folder and select Create Element. A dialog will open. Select Enumeration.

   

3. You are asked to choose a name for the enumeration:

   

4. To add literals to the enumeration, right-click on the enumeration, select Create Element, and select Enumeration Literal

   

5. Give the created literals names.

How to create Value Types

The specify a value type with its properties, follow these steps:

1. Navigate to the Data Types folder (or create it if it does not exist)

2. Right-click on the folder and select Create Element. A dialog will open. Select Value Type.

   

3. You are asked to choose a name for the value type:

   

4. To add properties to the value-type, right-click on the value-type, select Create Element, and select Property

   

5. Give the created propertie a name.

6. To give the property a type, right-click on the property, select Specification. A window will open. Select a type in the field Type.