Umple

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What Umple is

Umple is a free modeling tool and programming language family for model-oriented programming. It adds concepts such as associations, attributes, and state machines to object-oriented languages including Java, Python, C++, and PHP. Models can generate code and software engineering diagrams, including UML class and state diagrams, entity-relationship diagrams, state tables, formal methods code, and metrics. UmpleOnline supports browser-based editing, diagram and code generation, and model saving. A Docker image can run UmpleOnline locally in a browser, while the command-line compiler can be incorporated into toolchains such as Gradle or Ant. Listed command-line outputs include Java, PHP, Ruby, SQL, JSON, Ecore, TextUML, SCXML, and Yuml. The project is MIT-licensed. Local use on Mac, Linux, or Windows requires Java. The online service has no login mechanism, stores data in cookies and on a server, and makes model content accessible to site maintainers and people with or able to guess its URL. The service supports only a small number of files per session; its manual recommends using the command-line tool or an IDE for larger development work. The manual also says Umple is not validated for safety-critical or mission-critical use.

Who it suits

Umple suits students learning software design and developers modeling systems or generating code from readable abstractions. The browser editor is intended for exploration, while the command-line tool or an IDE is recommended for larger projects.

What it does well

Adds associations, attributes, and state machines to object-oriented languages.
Generates code and multiple software engineering diagrams.
UmpleOnline provides browser-based editing and code generation.
Docker can run UmpleOnline locally.
The project is MIT-licensed.

What to know first

Local use requires Java.
UmpleOnline supports only a small number of files per session.
Online model content can be accessed without login.
Not validated for safety-critical or mission-critical use.

Limits

UmpleOnline supports only a small number of Umple files per user session; the manual recommends the command-line tool or an IDE for serious development with many files. Cloud models and generated outputs are normally deleted after a few days, while permanent URLs are normally kept for two years after the last edit.

Getting started

Visit the Umple website or open UmpleOnline in a browser.
For local use on Mac, Linux, or Windows, install Java.
Choose a workflow: UmpleOnline, the command-line compiler, or a supported editor.
To run UmpleOnline locally, use its Docker image and connect to the local server from a browser.
Use the command-line compiler with a toolchain such as Gradle or Ant if needed.

Verdict

Umple combines model editing, diagram generation, and code generation, with browser, local Docker, and command-line options. Keep its online privacy limits and stated safety-critical restriction in mind when deciding where to use it.

Questions

Is Umple free?

Yes. Umple is free and open source under the MIT License.

Which platforms does Umple support?

The listed platforms include web, Windows, macOS, Linux, and Docker. Local use on Mac, Linux, or Windows requires Java.

What can Umple generate?

It can generate code and diagrams, including UML class and state diagrams, entity-relationship diagrams, state tables, formal methods code, and metrics. The command-line compiler lists Java, PHP, Ruby, SQL, JSON, Ecore, TextUML, SCXML, and Yuml as output targets.

Can Umple run locally?

Yes. The command-line compiler supports local use, and a Docker image can run UmpleOnline with a browser connecting to the local server.

Does UmpleOnline require an account?

No login mechanism is currently provided. Model content is accessible to site maintainers and anyone with or able to guess its URL.

Which editors does Umple support?

The manual lists Visual Studio Code, Zed, BBEdit, Neovim, and Sublime. The Eclipse plugin has not been maintained recently, and support may be dropped.

Facts from Umple's own pages

AI privacy: UmpleOnline states that its AI feature's API key is never sent to its server backend. · try.umple.org, 3 Oct 2026
Audience: The site says Umple can be used in real industry systems and has also helped students learn software design in the classroom. · umple.org, 4 Oct 2026
Availability: The project repository says Umple runs on Mac, Linux, and Windows and requires Java for local use. · github.com, 3 Oct 2026
Cloud data retention: UmpleOnline automatically stores models and generated outputs on Digital Research Alliance of Canada servers, normally deleting them after a few days; permanent URLs are normally kept for two years after the last edit. · cruise.umple.org, 4 Oct 2026
Code generation: Umple generates code in languages including Java, Python, PHP, Ruby, and C++; the manual notes that Ruby support is partial and C++ is still beta. · cruise.umple.org, 4 Oct 2026
Command line: The command-line compiler can be incorporated into toolchains using technologies such as Gradle or Ant. · cruise.umple.org, 3 Oct 2026
Data handling: UmpleOnline says it stores user data in cookies and on a server. · try.umple.org, 3 Oct 2026
Diagrams and analysis: Umple can generate UML class and state diagrams, entity-relationship diagrams, formal methods code, state tables, and metrics. · cruise.umple.org, 4 Oct 2026
Editors: The manual lists plugins or support for Visual Studio Code, Zed, BBEdit, Neovim, and Sublime; it says the Eclipse plugin has not been maintained recently and support may be dropped. · cruise.umple.org, 3 Oct 2026
Integrations: The manual describes support for Visual Studio Code, BBEdit, Zed, Neovim, Sublime, the command line, and an Eclipse plugin that has not been maintained recently. · cruise.umple.org, 4 Oct 2026
Intended users: The project describes Umple as usable for real systems in industry and says it has helped students learn software design in classrooms. · umple.org, 3 Oct 2026
License: The manual says all use of Umple and UmpleOnline is subject to the Umple MIT license. · cruise.umple.org, 4 Oct 2026
Local deployment: A Docker image can run UmpleOnline locally in a web browser, with model data stored on the user's machine. · cruise.umple.org, 4 Oct 2026
Local use: UmpleOnline can be run locally through a Docker image, with a browser connecting to a locally running server. · cruise.umple.org, 3 Oct 2026
Modeling: It adds abstractions such as associations, attributes, and state machines to object-oriented languages including Java, Python, C++, and PHP. · umple.org, 3 Oct 2026
Online editor: UmpleOnline lets users edit models in text or diagrams, generate code, and save examples in the cloud. · cruise.umple.org, 4 Oct 2026
Online limits: UmpleOnline is intended for exploration, particularly in education, and supports only a small number of Umple files per user session; the manual recommends the command-line tool or an IDE for serious development with many files. · cruise.umple.org, 4 Oct 2026
Outputs: The command-line compiler lists Java, PHP, Ruby, SQL, JSON, Ecore, TextUML, SCXML, and Yuml among its generation targets. · cruise.umple.org, 3 Oct 2026
Privacy: UmpleOnline currently has no login mechanism, and its manual says model content is accessible to site maintainers and anyone with or able to guess its URL. · cruise.umple.org, 4 Oct 2026
Purpose: Umple is a modeling tool and programming language family for Model-Oriented Programming. · umple.org, 3 Oct 2026
Security and compliance: The manual states that Umple is not validated for safety-critical or mission-critical use and should not be used for those purposes. · cruise.umple.org, 4 Oct 2026
Support: The site links to the user manual, question and help mailing lists, and GitHub issue reporting for help and problem reports. · umple.org, 4 Oct 2026
What it does: Umple is a modeling tool and programming language family for model-oriented programming that adds abstractions such as associations, attributes, and state machines to object-oriented languages. · umple.org, 4 Oct 2026

Where Umple stands on Freedom251

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