Transformation Editor

The Transformation Editor is a dedicated environment for writing and executing JjTL model-to-model transformations.

Opening the editor

Open the Transformation Editor from the project sidebar under Behaviour > Transforms. Click an existing transformation to edit it, or create a new one.

Editor layout

The editor has four areas:

• Source/Target selectors (top bar): choose the source and target metamodels
• Code editor (center): write JjTL transformation rules with syntax highlighting
• Metamodel browser (left): browse source and target metamodel structures side by side
• Suggested Mappings (right): AI-assisted mapping suggestions and grammar reference

Writing a transformation

A transformation starts with a header declaring its name and the source/target metamodels:

transformation MyTransformation

from SourceMetamodel
to   TargetMetamodel

Then add class mappings and attribute bindings. See the JjTL Reference for the full syntax.

Validation and execution

Click Validate to check the transformation for syntax errors. The Problems panel at the bottom shows errors and warnings.

Click Execute to run the transformation. Jjodel creates a new target model containing the transformation result. The Output panel shows execution details, timing, and any warnings.

Trace view

After execution, the Trace tab shows every mapping that was applied: which source elements produced which target elements, and whether each attribute mapping is invertible.

Use the search box to filter trace entries by class name or mapping rule.