Java 16 Crash "no ComponentUI class ..."

[tresf]

Starting with Java 16 (in this case, on MacOS 11 however others may be affected), this library throws the following error:

java.lang.Error: no ComponentUI class for: javax.swing.JOptionPane[,0,0,0x0,invalid,alignmentX=0.0,alignmentY=0.0,border=,flags=0,maximumSize=,minimumSize=,preferredSize=,icon=,initialValue=,message=test,messageType=INFORMATION_MESSAGE,optionType=DEFAULT_OPTION,wantsInput=false]
	at java.desktop/javax.swing.UIDefaults.getUIError(UIDefaults.java:762)
	at java.desktop/javax.swing.MultiUIDefaults.getUIError(MultiUIDefaults.java:144)
	at java.desktop/javax.swing.UIDefaults.getUI(UIDefaults.java:792)
	at java.desktop/javax.swing.UIManager.getUI(UIManager.java:1069)
	at java.desktop/javax.swing.JOptionPane.updateUI(JOptionPane.java:1873)
	at java.desktop/javax.swing.JOptionPane.<init>(JOptionPane.java:1838)
	at java.desktop/javax.swing.JOptionPane.showOptionDialog(JOptionPane.java:862)
	at java.desktop/javax.swing.JOptionPane.showMessageDialog(JOptionPane.java:670)
	at java.desktop/javax.swing.JOptionPane.showMessageDialog(JOptionPane.java:641)
	at java.desktop/javax.swing.JOptionPane.showMessageDialog(JOptionPane.java:612)
	at qz.Test.lambda$main$0(Test.java:9)
	at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:306)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:770)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:715)
	at java.base/java.security.AccessController.doPrivileged(AccessController.java:391)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
	at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:740)
	at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
	at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)

This error may vary but it is reproducible with the following JDKs:

• Zulu 16
• AdoptOpenJDK 16
• Homebrew's OpenJDK 16

Code to reproduce:

public static void main(String ... args) throws Throwable {
   UIManager.setLookAndFeel("com.bulenkov.darcula.DarculaLaf");
   SwingUtilities.invokeAndWait(() -> {
      JOptionPane.showMessageDialog(null, "test");
   });
}

Commenting out the line UIManager.setLookAndFeel will prevent the crash.

[tresf]

A workaround, add the following JVM property:

--add-exports java.desktop/sun.swing=ALL-UNNAMED

... and if on macOS, also add:

--add-exports java.desktop/com.apple.laf=ALL-UNNAMED