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UML & SysML Tools

Design object oriented software with Unified Modeling Language (UML).

Use Case Diagram

Capture functional requirements with UML use case diagram. Each use case in a use case diagram represents a high level business goal that yields a measurable result of business values. (UML) Actors are connected with use cases to represent the roles that interact with the functions.

Use case diagram

Class Diagram

Model the structure of system by modeling its classes, their attributes and operations in a UML class diagram. UML class diagram is a blueprint of the classes (code level) required to build a software system. Programmers implement a software system with the help of both the class diagram and the class specification.

Class diagram

Sequence Diagram

Visualize the interactions between users, systems and sub-systems over time through message passing between objects or roles. If class diagram represents the skeleton of classes by showing their attributes and methods, UML sequence diagram complete the classes by representing the programming logic to be filled in methods' body.

Sequence diagram

Communication Diagram

Collaboration between objects in runtime can be modeled in the UML tool, with a UML communication diagram. In a communication diagram, objects, called lifelines, are connected to represent the need of communication during the execution of an interaction. Messages can be added on top of the connectors to list the calls made from and to those lifelines.

Communication diagram
Activity diagram

Activity Diagram

Use UML activity diagram, the flowchart-based diagram to model the flow of control. Partition actions according to the type of participant involved.

State Machine Diagram

State machine diagram is a critical design model for event-driven systems. Well-designed state machine shows accurately the essential states of objects as well as the triggers of state change, which facilitates the development of error-free state machine.


Protocol state machine specification

Model how a protocol works, with protocol state machine. Both behavioral and protocol state machines are supported in the UML tool.

State machine diagram

Component Diagram

Components diagrams are used to model the structure of systems by showing how little parts of the system gear up in forming a bigger part, or forming the entire software systems.

Component diagram

Deployment Diagram

Models the physical deployment of software components with UML deployment diagram. In deployment diagram, hardware components (e.g. web server, mail server, application server) are presented as nodes, with the software components that run inside the hardware components presented as artifacts.

Deployment diagram
Package diagram

Package Diagram

Arrange and organize model for large-scale project with package diagrams. Package diagram is also good in visualizing structure and dependency between sub-systems or modules.

Object Diagram

View a snapshot of instances of classifiers in UML class diagrams. Similar to class diagrams, object diagrams show the static design of a system from a prototypical perspective.

Object diagram

Composite Structure Diagram

Visualize the internal structure of a class or collaboration with UML composite structure diagram. Model a system from a micro point-of-view using UML composite structure diagram.

Composite structure diagram

Timing Diagram

Timing diagrams model the behavior of objects throughout a given period of time. It is a commonly used UML tool for designing real-time and distributed systems.


Adjustable time unit

Drag to move a time unit back and forth. Have a timing frame updated automatically according to your change.

Timing diagram
Interaction Overview

Interaction Overview Diagram

View the sequence of interactions with UML interaction overview diagram. Interaction overview diagram helps represent complex scenario that involve multiple interactions presented as multiple UML sequence diagrams.


Show diagram thumbnail in interaction overview

View the thumbnail of interaction diagrams or sequence diagrams. View and know the control flows of interactions.

SysML requirement diagram

SysML Requirement Diagram

Requirement is what your clients want and what your team have to fulfill. It is so important that needs to be managed carefully. The SysML requirement diagram provides a visual approach in representing and managing system requirements. In a requirement diagram, requirements are shown as blocks, with connectors in between, illustrating the derivation, dependency and grouping of requirements.


User-defined requirement types

Define your own requirement types, with user-defined properties and appearance.


Export and import requirements to Excel

Produce a list of requirement to Excel for external manipulation. Import the file back for updating.

Block Definition Diagram

Visualize your system hierarchy. Define the system/component classifications in blocks to get a better picture of interconnections between these system components.

Block definition diagram

Internal Block Diagram

Take a closer look at your system design. Describe the internal structure of a system in terms of its parts, ports, and connectors.

Internal block diagram

Parametric Diagram

Parametric Diagram is a restricted form of internal block diagram that shows only the use of constraint blocks along with the properties they constrain within a context. Parametric diagram is used to support engineering analysis, such as performance, reliability, and mass properties analysis.

Use case diagram
Model element referencing

Model Element Referencing


Add internal references between diagrams, shapes, model elements

Make internal links between different kinds of project artifacts. Those references work both in Visual Paradigm and in any document and Web contents generated from your design.


Add external reference to business documents

Maintain reference between software design and the business documents to help find out why a design decision was made.


Mark in shape body when have reference added

Glance over a design. The tiny marker that appear in shapes' body indicates that the shapes have references added.


Reference model element in description

Insert model element references to rich text description. The referenced model elements will be linked and highlighted.

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