Séquence Usecase Classe Activité Composant État Objet Déploiement Temps Regex Network Wireframe Archimate Gantt MindMap WBS EBNF JSON YAML
PlantUML Advanced usage Eclipse Layout Kernel
🧩
New! Render PlantUML diagrams directly inside GitHub with our official browser extension — No server. No tokens. No tracking. Zero permissions but clipboard. — Try it out and let us know what you think!
Add to Chrome Add to Firefox

Edit in DokuwikiEdit in AsciidocEdit in Markdown
Eclipse Layout Kernel

PlantUML uses an external layout engine for some diagrams (classes, use cases...). By default, GraphViz/dot is used. This means that PlantUML has to call an external process to generate some diagrams.

There are some work in progress to change this behavior. For example, a port of GraphViz to Java is ongoing.

Recently, Hallvard Trætteberg teaches us on how to use Eclipse Layout Kernel as a library to process the layout.

This is still alpha-software, but results are very interesting. This is working starting from V1.2021.5.

Edit in DokuwikiEdit in AsciidocEdit in Markdown
Requirement

From V1.2021.5 to V1.2024.6

ELK is distributed as an independent library. So you have to build it yourself, or you can download the complete jar file here.

Both plantuml.jar and elk-full.jar have to be in the very same folder. You cannot rename elk-full.jar

Since V1.2024.6

Since V1.2024.6, ELK is directly included on the PlantUML package and on the plantuml.jar.

[Ref. GH-1813]

Edit in DokuwikiEdit in AsciidocEdit in Markdown
Usage

Then you can invoke ELK instead of Graphviz with the !pragma layout elk directive.

Example:

This diagram is generated using ELK.

You can use the -P command-line option to specify the pragma, rather than putting it in the puml file: 

java -jar plantuml.jar -Playout=elk

[Ref. GH-582]

Do not expect too much right now, this is really an alpha-version. The idea is to get feedback from users, to know if we should continue in this direction (that is, supporting ELK within PlantUML).

Still, you can test class diagram and deployment diagram and tell us what you think about the result.

Edit in DokuwikiEdit in AsciidocEdit in Markdown
Alternative layout engines

See smetana and vizjs for other alternatives to graphviz-dot.