Fix null pointer and other exceptions in schema view

Quasar985 commented 3 weeks ago

Prerequisites

[x] Reviewed the checklist
[x] Reviewed feedback from the "Sonar Cloud" bot. Note that you have to wait for the "CI / Unit Tests") to complete first. Failed Unit tests can be debugged by adding the label "verbose logging" to the GitHub PR.

Description of the Change

Added synchronize to functions so that rapid closing and opening of schema view doesn't throw errors.

Alternate Designs

N/A

Why Should This Be In Core?

N/A

Benefits

Bug fixes

Possible Drawbacks

None

Verification Process

Open consty
Open a graph
Rapidly open and close schema view (schema view can be opened with ctrl-shift-s)
Observe no exceptions are thrown

Applicable Issues

https://github.com/constellation-app/constellation/issues/2144

antares1470 commented 2 weeks ago

Another observation I made was that if you spam it enough times, there comes a point where the schema view starts to lag while trying to load (mostly when you got to memory limits) and to the point that it doesn't really load properly

Quasar985 commented 1 week ago

Still managed to get:

java.lang.NullPointerException: Cannot read field "children" because the return value of "javafx.scene.Node.getParent()" is null

javafx.graphics/javafx.scene.Parent$2.onChanged(Parent.java:340)
javafx.base/com.sun.javafx.collections.TrackableObservableList.lambda$new$0(TrackableObservableList.java:44)
javafx.base/com.sun.javafx.collections.ListListenerHelper$Generic.fireValueChangedEvent(ListListenerHelper.java:327)
javafx.base/com.sun.javafx.collections.ListListenerHelper.fireValueChangedEvent(ListListenerHelper.java:71)
javafx.base/javafx.collections.ObservableListBase.fireChange(ObservableListBase.java:246)
javafx.base/javafx.collections.ListChangeBuilder.commit(ListChangeBuilder.java:482)
javafx.base/javafx.collections.ListChangeBuilder.endChange(ListChangeBuilder.java:541)
javafx.base/javafx.collections.ObservableListBase.endChange(ObservableListBase.java:210)
javafx.base/javafx.collections.ModifiableObservableListBase.addAll(ModifiableObservableListBase.java:117)
javafx.base/com.sun.javafx.collections.VetoableListDecorator.addAll(VetoableListDecorator.java:241)
javafx.base/com.sun.javafx.collections.VetoableListDecorator.addAll(VetoableListDecorator.java:105)
javafx.graphics/javafx.scene.layout.VBox.<init>(VBox.java:240)
au.gov.asd.tac.constellation.views.schemaview.providers.VertexTypeNodeProvider.addFilter(VertexTypeNodeProvider.java:216)
au.gov.asd.tac.constellation.views.schemaview.providers.VertexTypeNodeProvider.setContent(VertexTypeNodeProvider.java:272)
au.gov.asd.tac.constellation.views.schemaview.SchemaViewPane.lambda$populate$0(SchemaViewPane.java:58)

Was following the reproducer you outlined (i.e. spamming Schema View open and close very quickly)

99% sure I've fixed with the newest commit. I tested with an auto-clicker that is able to open and close the schema view many times a second. This error rarely showed up to begin with, but I reckon I've got it fixed.