History & persistence

Move along Protégé’s shared undo/redo stack and save the active ontology to disk. Because every model edit made by the other tools goes through OWLModelManager.applyChanges, undo_change / redo_change step the same history as the GUI’s Edit ▸ Undo / Redo.

Table of contents

1. undo_change
2. redo_change
3. save_ontology

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undo_change

Undo the last change on Protégé’s shared undo stack. Reports the net axiom-count change so the caller can see what the undo did. Fails if there is nothing to undo.

Mutating (moves the shared history).

Arguments

None.

Returns

• undone: boolean — always true on success.
• message: string — human-readable summary.
• axioms_before: integer — total axiom count before the undo.
• axioms_after: integer — total axiom count after the undo.
• net_axiom_change: integer — axioms_after − axioms_before.
• can_undo: boolean — whether more undo steps remain.
• can_redo: boolean — whether a redo is now available.

If the undo stack is empty, returns an error object: { "error": "Nothing to undo." }.

Example

{}

redo_change

Redo the last undone change on Protégé’s shared undo stack (also reports the net axiom-count change). Fails if there is nothing to redo.

Mutating (moves the shared history).

Arguments

None.

Returns

• redone: boolean — always true on success.
• message: string — human-readable summary.
• axioms_before: integer — total axiom count before the redo.
• axioms_after: integer — total axiom count after the redo.
• net_axiom_change: integer — axioms_after − axioms_before.
• can_undo: boolean — whether an undo is available.
• can_redo: boolean — whether more redo steps remain.

If there is nothing to redo, returns an error object: { "error": "Nothing to redo." }.

Example

{}

save_ontology

Save the active ontology to disk. With no arguments it writes to the ontology’s existing document; a never-saved (untitled) ontology has no file yet, so pass path to choose one (save-as). The serialization format is inferred from the file extension (.ttl, .owl / .rdf / .xml, .omn, .ofn, .owx) or falls back to the ontology’s current format. After a save-as, the ontology is bound to that file, so later argument-less saves go to the same place.

Persistence (writes a file; not an undoable model change).

Arguments

Name	Type	Required	Default	Description
path	string	no	—	File path to save to (save-as), e.g. /tmp/pets.ttl. Omit to write to the existing document.

Returns

• saved: boolean — true on success.
• path: string — the absolute path written.
• format: string — the serialization format used (the format class’s simple name).

Returns an error object if the ontology has never been saved and no path was given, or if the target directory cannot be created.

Example

{ "path": "/tmp/pets.ttl" }