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NPE when adding stylesheets

See original GitHub issue

For my new ShowcaseFX view / app I constantly need to add and remove stylesheets. When doing to I keep getting this NPE:

Exception in thread "JavaFX Application Thread" java.lang.NullPointerException
	at java.base/java.util.regex.Matcher.getTextLength(Matcher.java:1770)
	at java.base/java.util.regex.Matcher.reset(Matcher.java:416)
	at java.base/java.util.regex.Matcher.<init>(Matcher.java:253)
	at java.base/java.util.regex.Pattern.matcher(Pattern.java:1133)
	at fr.brouillard.oss.cssfx@11.5.0/fr.brouillard.oss.cssfx.impl.CSSFXMonitor$URIRegistrar.classpathToURI(CSSFXMonitor.java:319)
	at fr.brouillard.oss.cssfx@11.5.0/fr.brouillard.oss.cssfx.impl.CSSFXMonitor$URIRegistrar.register(CSSFXMonitor.java:342)
	at fr.brouillard.oss.cssfx@11.5.0/fr.brouillard.oss.cssfx.impl.CSSFXMonitor$StyleSheetChangeListener.onChanged(CSSFXMonitor.java:399)
	at javafx.base/com.sun.javafx.collections.ListListenerHelper$Generic.fireValueChangedEvent(ListListenerHelper.java:329)
	at javafx.base/com.sun.javafx.collections.ListListenerHelper.fireValueChangedEvent(ListListenerHelper.java:73)
	at javafx.base/javafx.collections.ObservableListBase.fireChange(ObservableListBase.java:239)
	at javafx.base/javafx.collections.ListChangeBuilder.commit(ListChangeBuilder.java:482)
	at javafx.base/javafx.collections.ListChangeBuilder.endChange(ListChangeBuilder.java:541)
	at javafx.base/javafx.collections.ObservableListBase.endChange(ObservableListBase.java:211)
	at javafx.base/javafx.collections.ModifiableObservableListBase.addAll(ModifiableObservableListBase.java:109)
	at com.dlsc.showcasefx@0.0.6/com.dlsc.showcase.impl.CssShowcaseViewSkin.updateStylesheets(CssShowcaseViewSkin.java:103)
	at com.dlsc.showcasefx@0.0.6/com.dlsc.showcase.impl.CssShowcaseViewSkin.lambda$new$0(CssShowcaseViewSkin.java:90)

Issue Analytics

State:
Created 2 years ago
Comments:8 (4 by maintainers)

Top GitHub Comments

1reaction

dlemmermanncommented, Jan 26, 2022

Never mind … I found out what the issue was. My code was adding multiple configurations to the view when dropping multiple files. One config per file. This then caused each config to be selected, which removed the stylesheets from the previous config, and so on … obviously messy.

0reactions

dlemmermanncommented, Jan 26, 2022

I only get the error when I do a drag and drop of MULTIPLE css files at the same time.

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