ADDITIONAL SYSTEM INFORMATION :
Using OpenJFX 15 on AdoptOpenJDK 15

A DESCRIPTION OF THE PROBLEM :
FXMLLoader fails to load a sub layout using `fx:include` with the `resources` attribute.

parent.fxml:

<?import javafx.scene.layout.AnchorPane?>
<AnchorPane xmlns:fx="http://javafx.com/fxml">
    <children>
        <fx:include source="child.fxml" resources="home.properties"/>
    </children>
</AnchorPane>

child.fxml (empty pane):

<?import javafx.scene.layout.AnchorPane?>
<AnchorPane xmlns:fx="http://javafx.com/fxml">
</AnchorPane>

Generates the following error at runtime:

Exception in Application start method
...
Caused by: java.lang.NullPointerException
at java.base/java.util.ResourceBundle.getBundle(ResourceBundle.java:1281)
at javafx.fxml/javafx.fxml.FXMLLoader$IncludeElement.processAttribute(FXMLLoader.java:1103)
at javafx.fxml/javafx.fxml.FXMLLoader$Element.processStartElement(FXMLLoader.java:229)
at javafx.fxml/javafx.fxml.FXMLLoader$ValueElement.processStartElement(FXMLLoader.java:754)
at javafx.fxml/javafx.fxml.FXMLLoader.processStartElement(FXMLLoader.java:2808)
at javafx.fxml/javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2634)
... 16 more

After inspecting FXMLLoader.java and ResourceBundle.java at those lines it's apparent FXMLLoader needs to call a different overload of getBundle when .getClassLoader() is null (happens if the parent class was loaded by the bootstrap loader). I'll submit a PR on GitHub for this.


FREQUENCY : always