AudioSystem,isAudioLineSupported returns false

I am trying to use some Java audio code that worked back in 2019. I am now using the Eclipse IDE with JavaSE-21 running on Windows 11. The following code is not working:

AudioFormat af = makeAudioFormat(); DataLine.Info info = new DataLine.Info(TargetDataLine.class, af); if (!AudioSystem.isLineSupported(info)) { System.out.println("Unsupported audio format"); System.out.println(info); }

The println outputs this information:

Unsupported audio format interface TargetDataLine supporting format PCM_SIGNED 44100.0 Hz, 16 bit, mono, 2 bytes/frame, big-endian

I have tried mono/stereo and big-endian/little-endian: they all fail.

After looking at the Oracle documentation I tried this code:

if (AudioSystem.isLineSupported(Port.Info.MICROPHONE)) {

It also fails with Port.Info.LINE_IN.

Audio input definitely works with Audacity, and with the C program that I wish to replace The C program uses the line settings that I have specified here.

In Settings/Privacy & Security/Microphone, "let apps access your microphone" is enabled, and I can see records of Audacity and my C program using the microphone, but there is no reference to the Java app.

If I go on and try to use the TargetDataLine anyway, I get the following stack trace:

Exception in thread "AWT-EventQueue-0" java.lang.IllegalArgumentException: No line matching interface TargetDataLine supporting format PCM_SIGNED 44100.0 Hz, 16 bit, mono, 2 bytes/frame, big-endian is supported. at java.desktop/javax.sound.sampled.AudioSystem.getLine(AudioSystem.java:423) at foo.recorder.AudioIn.<init>(AudioIn.java:75) at foo.recorder.RecorderTab.startRecord(RecorderTab.java:379) at foo.recorder.RecorderTab$6.buttonPressed(RecorderTab.java:364) at foo.recorder.NoteClickImage$Listener.onClick(NoteClickImage.java:23) at foo.recorder.ClickListener.mouseClicked(ClickListener.java:12) at java.desktop/java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:280) at java.desktop/java.awt.Component.processMouseEvent(Component.java:6624) at java.desktop/javax.swing.JComponent.processMouseEvent(JComponent.java:3398) at java.desktop/java.awt.Component.processEvent(Component.java:6386) at java.desktop/java.awt.Container.processEvent(Container.java:2266) at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:4996) at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2324) at java.desktop/java.awt.Component.dispatchEvent(Component.java:4828) at java.desktop/java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4948) at java.desktop/java.awt.LightweightDispatcher.processMouseEvent(Container.java:4584) at java.desktop/java.awt.LightweightDispatcher.dispatchEvent(Container.java:4516) at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2310) at java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2780) at java.desktop/java.awt.Component.dispatchEvent(Component.java:4828) at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:775) at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:720) at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:714) at java.base/java.security.AccessController.doPrivileged(AccessController.java:400) at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:87) at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:98) at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:747) at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745) at java.base/java.security.AccessController.doPrivileged(AccessController.java:400) at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:87) at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:744) 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)

I have read that this exception can also be caused by a security issue.