XDiagram

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WebMD - Better information. Me.xDiagram.Connections(0).ConnectionPoints(0) = New Point(100, 100) Me.xDiagram.Connections(0).ConnectionPoints(1) = New Point(220, 200) Me.xDiagram.Connections(0).IsModified = True If you don't want to manually traverse the ConnectionPoints collection and then set the IsModified property, you can use the. XDiagram is a user-oriented Mac application that promises to help you create beautiful UML diagrams quickly and effortlessly. UML, short for Unified Modeling Language, is a straightforward modeling language, which includes a set of graphic notation techniques used in the creation of visual models. Basketball Court Dimensions. Basketball-Goals.com specializes in supplying the finest basketball equipment at the best prices. One of our best selling products is basketball court tile check out the Harlem Globetrotters playing on our backyard basketball court tile or design a court for your backyard just visit our court designer. Xdiagram DSL Primitives In order to use Xdiagram there must exist a metamodel described in EMF that represents the abstract syntax of the DSML for which one wants to develop support for graphical.

This section describes some basic concepts you should be familiar with when developing with FXDiagram.

XDiagram

Scenegraph

The baseclasses for the nodes of the scenegraph are located in the de.fxdiagram.core package. JavaFX is based on abstract classes, so all for the scenegraph inherit from javafx.scene.Parent.
A XDiagramis a container for XNodes and XConnections. XDiagram#nodes and XDiagram#connections are life collections: When an element is added/removed, it is automatically added/removed to/from the JavaFX scenegraph. Diagrams can only be nested when they are contained in nodes (see OpenableDiagramNode).

Clients usually implement their own subclasses of XNode for custom graphics and behavior. Cba sophos support. The class hierarchy will point you to a lot of examples.

XConnections can either be polylines or quadratic/cubic Bézier splines. The can have XConnectionLabels which are by default layouted tangent to the line and a source and target decoration. There is usually no need to extend XConnection.

XShape is the superclass of XNode and XConnection. The lifecycle methods of a shape is:

  1. Creation by using a constructor.
  2. The domain object is set.
  3. The graphical node is created (createNode).
  4. The shape is connected to a diagram (initializeGraphics).
  5. The shape is activated (activate) to react to user actions.
  6. The shape is removed from the scenegraph.

The diagram is a child of an XRoot. It holds an overlay heads up display, the menu or services like the domain object providers. The root can be directly added to the javafx.scene.Scene.

XDiagram

FxProperty

FXDiagram defines a number of so called active annotations, which allow to participate in the Xtend to Java transpilation step. One of these annotations is @FxProperty for fields. This will automatically create a getter and setter with the plain Java type as well as a method to access the JavaFX property. For more details have a look at the generated Java code. Examples:

Type inference will not work for @FxProperty fields.

Helper classes

The package de.fxdiagram.core.extensions contains classes with static helper methods. These are usually imported as import static extension and add functionality to JavaFX based classes, e.g. CoreExtensions offers methods to navigate to the root or the diagram of a shape.

Behavior

XDiagram

A Behavior is a piece of user interaction provided by an XShape. The shape can have any number of behaviors. They are registered in the doActviate method. A behavior usually registers event listeners and binds to Java properties.

Domain Objects

Both XNodeand XConnection store a reference to a domain object by means of a DomainObjectDescriptor. This indirection is necessary for two reasons: It is often not a good idea to store hard references e.g. to EMF or to database objects, and we need a way to persist arbitrary kinds of domain objects when we store the diagram.

To allow the use of domain objects that can only be safely read in a transaction, there is
the DomainObjectDescriptorImpl.withDomainObject method. It will open an appropriate transaction execute the given lambda close the transaction and return the result. Whether this method is reentrant or not depends on the specific implementation.

A DomainObjectProvider converts between the real domain object and its descriptor. It can store additional information needed to resolve/retrieve the object, such as a database connection or a classpath. Domain object providers are registered to the XRootin order to be resolvable.

Persistence

FXDiagram does not have its own diagram model. Instead, it uses a reflective method to serialize the JavaFX scenegraph directly in JSON notation. But not every property of a node has to be saved. Many of them can be recovered/calculated from the domain object or some defaults. As users should be able to create arbitrary shapes using the full power of JavaFX, there needs to be a way to tell the system which properties are important for saving.

This is exactly the purpose of the @ModelNode annotation. For example the annotation

tells FXDiagram to save the values of the properties layoutX, layoutY and type for an object of class XControlPoint in the scenegraph. By default, all model node properties of the supertype are serialized as well.

Technically, @ModelNode is an active annotation for classes that creates a default constructor, adds the interface XModelProvider and implements its method populate() to populate the model that is saved with the values of the specified properties. If you implement a scenegraph node in Java, you have to do all this by hand.

Animation Commands

Undo/Redo is implemented by using the command pattern: All modifications are wrapped into command objects that can be executed, undone and redone. These are stored on a command stack. In FXDiagram the command stack is located in the XRoot of the diagram.

What makes FXDiagram different is that it does not just wrap some model changes, but uses a more user-centric approach: When you undo a change, you want to rewind your work to a specific prior state. FXDiagram restores the viewport you had when that change was finished and then uses a smooth transition undoing the modification. The user does not get lost and can easily identify the right point in time.

To implement that, all commands offer three animations (execute, undo, redo). Animations are queued for sequential playback. That means that when you create your own commands, you have to be aware that the current state of the diagram may not be the same as the one when the animation actually starts. Storing and restoring the viewport happens automatically when you inherit from AbstractAnimationCommand.

A graphical media player panel allows to undo/redo changes. It can be reached via the context menu or by pressing CTRL-P (CMD-Pon Mac).

Menu Actions

Diagrama

FXDiagram has a graphical context menu that is activated by right-clicking on an empty space in the diagram. It is populated with DiagramActions. Actions can also be triggered by keyboard shortcuts. They are registered by adding them to the XRoot#getDiagramActionRegistry().

Hierarchy of UML 2.5 Diagrams, shown as a class diagram. The individual classes are represented just with one compartment, but they often contain up to three compartments.

In software engineering, a class diagram in the Unified Modeling Language (UML) is a type of static structure diagram that describes the structure of a system by showing the system's classes, their attributes, operations (or methods), and the relationships among objects.

The class diagram is the main building block of object-oriented modeling. It is used for general conceptual modeling of the structure of the application, and for detailed modeling translating the models into programming code. Class diagrams can also be used for data modeling.[1] The classes in a class diagram represent both the main elements, interactions in the application, and the classes to be programmed.

In the diagram, classes are represented with boxes that contain three compartments:

  • The top compartment contains the name of the class. It is printed in bold and centered, and the first letter is capitalized.
  • The middle compartment contains the attributes of the class. They are left-aligned and the first letter is lowercase.
  • The bottom compartment contains the operations the class can execute. They are also left-aligned and the first letter is lowercase.
A class with three compartments.

In the design of a system, a number of classes are identified and grouped together in a class diagram that helps to determine the static relations between them. With detailed modeling, the classes of the conceptual design are often split into a number of subclasses.

In order to further describe the behavior of systems, these class diagrams can be complemented by a state diagram or UML state machine.[2]

Members[edit]

UML provides mechanisms to represent class members, such as attributes and methods, and additional information about them like constructors.

Visibility[edit]

To specify the visibility of a class member (i.e. any attribute or method), these notations must be placed before the member's name:[3]

+Public
-Private
#Protected
~Package

A derived property is a property whose value (or values) is produced or computed from other information, for example, by using values of other properties.

A derived property is shown with its name preceded by a forward slash '/'. [4]

Scope[edit]

The UML specifies two types of scope for members: instance and classifier, and the latter is represented by underlined names.[5]

  • Classifier members are commonly recognized as “static” in many programming languages. The scope is the class itself.
    • Attribute values are equal for all instances
    • Method invocation does not affect the classifier’s state
  • Instance members are scoped to a specific instance.
    • Attribute values may vary between instances
    • Method invocation may affect the instance’s state (i.e. change instance’s attributes)

To indicate a classifier scope for a member, its name must be underlined. Otherwise, instance scope is assumed by default.

Relationships[edit]

UML relations notation

A relationship is a general term covering the specific types of logical connections found on class and object diagrams. UML defines the following relationships:

Instance-level relationships[edit]

Dependency[edit]

A dependency is a semantic connection between dependent and independent model elements.[6] It exists between two elements if changes to the definition of one element (the server or target) may cause changes to the other (the client or source). This association is uni-directional. A dependency is displayed as a dashed line with an open arrow that points from the client to the supplier.

Association[edit]

Class diagram example of association between two classes

An association represents a family of links. A binary association (with two ends) is normally represented as a line. An association can link any number of classes. An association with three links is called a ternary association. An association can be named, and the ends of an association can be adorned with role names, ownership indicators, multiplicity, visibility, and other properties.
There are four different types of association: bi-directional, uni-directional, aggregation (includes composition aggregation) and reflexive. Bi-directional and uni-directional associations are the most common ones.
For instance, a flight class is associated with a plane class bi-directionally. Association represents the static relationship shared among the objects of two classes.

Aggregation[edit]

Class diagram showing Aggregation between two classes. Here, a Professor 'has a' class to teach.

Aggregation is a variant of the 'has a' association relationship; aggregation is more specific than association. It is an association that represents a part-whole or part-of relationship. As shown in the image, a Professor 'has a' class to teach. As a type of association, an aggregation can be named and have the same adornments that an association can. However, an aggregation may not involve more than two classes; it must be a binary association. Furthermore, there is hardly a difference between aggregations and associations during implementation, and the diagram may skip aggregation relations altogether.[7]

Aggregation can occur when a class is a collection or container of other classes, but the contained classes do not have a strong lifecycle dependency on the container. The contents of the container still exist when the container is destroyed.

In UML, it is graphically represented as a hollowdiamond shape on the containing class with a single line that connects it to the contained class. The aggregate is semantically an extended object that is treated as a unit in many operations, although physically it is made of several lesser objects.

Example: Library and Students. Here the student can exist without library, the relation between student and library is aggregation.

Composition[edit]

Two class diagrams. The diagram on top shows Composition between two classes: A Car has exactly one Carburetor, and a Carburetor is a part of one Car. Carburetors cannot exist as separate parts, detached from a specific car. The diagram on bottom shows Aggregation between two classes: A Pond has zero or more Ducks, and a Duck has at most one Pond (at a time). Duck can exist separately from a Pond, e.g. it can live near a lake. When we destroy a Pond we usually do not kill all the Ducks.

The UML representation of a composition relationship shows composition as a filled diamond shape on the containing class end of the lines that connect contained class(es) to the containing class.

Differences between Composition and Aggregation[edit]

Composition relationship
1. When attempting to represent real-world whole-part relationships, e.g. an engine is a part of a car.
2. When the container is destroyed, the contents are also destroyed, e.g. a university and its departments.
Aggregation relationship
1. When representing a software or database relationship, e.g. car model engine ENG01 is part of a car model CM01, as the engine, ENG01, may be also part of a different car model.[8]
2. When the container is destroyed, the contents are usually not destroyed, e.g. a professor has students; when the professor dies the students do not die along with them.

Thus the aggregation relationship is often 'catalog' containment to distinguish it from composition's 'physical' containment.

Class-level relationships[edit]

Generalization/Inheritance[edit]

Class diagram showing generalization between the superclass Person and the two subclasses Student and Professor

It indicates that one of the two related classes (the subclass) is considered to be a specialized form of the other (the super type) and the superclass is considered a Generalization of the subclass. In practice, this means that any instance of the subtype is also an instance of the superclass. An exemplary tree of generalizations of this form is found in biological classification: humans are a subclass of simian, which is a subclass of mammal, and so on. The relationship is most easily understood by the phrase 'an A is a B' (a human is a mammal, a mammal is an animal).

The UML graphical representation of a Generalization is a hollow triangle shape on the superclass end of the line (or tree of lines) that connects it to one or more subtypes.

The generalization relationship is also known as the inheritance or 'is a' relationship.

The superclass (base class) in the generalization relationship is also known as the 'parent', superclass, base class, or base type.

Diagram Mac

The subtype in the specialization relationship is also known as the 'child', subclass, derived class, derived type, inheriting class, or inheriting type.

Note that this relationship bears no resemblance to the biological parent–child relationship: the use of these terms is extremely common, but can be misleading.

A is a type of B
For example, 'an oak is a type of tree', 'an automobile is a type of vehicle'

Generalization can only be shown on class diagrams and on use case diagrams.

Realization/Implementation[edit]

In UML modelling, a realization relationship is a relationship between two model elements, in which one model element (the client) realizes (implements or executes) the behavior that the other model element (the supplier) specifies.

The UML graphical representation of a Realization is a hollow triangle shape on the interface end of the dashed line (or tree of lines) that connects it to one or more implementers. A plain arrow head is used on the interface end of the dashed line that connects it to its users. In component diagrams, the ball-and-socket graphic convention is used (implementors expose a ball or lollipop, whereas users show a socket).Realizations can only be shown on class or component diagrams.A realization is a relationship between classes, interfaces, components and packages that connects a client element with a supplier element. A realization relationship between classes/components and interfaces shows that the class/component realizes the operations offered by the interface.

General relationship[edit]

Class diagram showing dependency between 'Car' class and 'Wheel' class (An even clearer example would be 'Car depends on Wheel', because Car already aggregates (and not just uses) Wheel)

Dependency[edit]

Dependency is a weaker form of bond that indicates that one class depends on another because it uses it at some point in time.One class depends on another if the independent class is a parameter variable or local variable of a method of the dependent class. This is different from an association, where an attribute of the dependent class is an instance of the independent class. Sometimes the relationship between two classes is very weak. They are not implemented withmember variables at all. Rather they might be implemented as member function arguments.

Multiplicity[edit]

This association relationship indicates that (at least) one of the two related classes make reference to the other. This relationship is usually described as 'A has a B' (a mother cat has kittens, kittens have a mother cat).

The UML representation of an association is a line connecting the two associated classes. At each end of the line there is optional notation. For example, we can indicate, using an arrowhead that the pointy end is visible from the arrow tail. We can indicate ownership by the placement of a ball, the role the elements of that end play by supplying a name for the role, and the multiplicity of instances of that entity (the range of number of objects that participate in the association from the perspective of the other end).

0No instances (rare)
0.1No instances, or one instance
1Exactly one instance
1.1Exactly one instance
0.*Zero or more instances
*Zero or more instances
1.*One or more instances

Analysis stereotypes[edit]

Entities[edit]

Entity classes model long-lived information handled by the system, and sometimes the behavior associated with the information. They should not be identified as database tables or other. Retrieved 8 September 2011.

  • ^Scott W. Ambler (2009) UML 2 Class Diagrams. Webdoc 2003-2009. Accessed Dec 2, 2009
  • ^UML Reference Card, Version 2.1.2, Holub Associates, August 2007, retrieved 12 March 2011
  • ^'UML derived property is property which value is produced or computed from other information, for example, by using other properties'. www.uml-diagrams.org. Retrieved 2019-01-24.
  • ^OMG Unified Modeling Language (OMG UML) Superstructure, Version 2.3: May 2010. Retrieved 23 September 2010.
  • ^Fowler (2003) UML Distilled: A Brief Guide to the Standard Object Modeling Language
  • ^'UML Tutorial part 1: class diagrams'(PDF). Archived from the original(PDF) on 2007-01-03. Retrieved 2015-07-18.
  • ^Goodwin, David. 'Modelling and Simulation, p. 26'(PDF). The University of Warwick. Retrieved 28 November 2015.
  • External links[edit]

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