Random java errors on a mac matlab 2015

On matlab 2015a on a mac (capitan) I randomly get a very long list of Java errors listed below:

Sometimes, Matlab freezes after that, sometimes now. These errors show sometimes directly upon startup, sometimes after working on it for a while. Sometimes in connection to psychtoolbox (as psychtoolbox scripts are running), but also when doing different things (like simply writing on the editor). They also occurr after fresh installing matlab, and before installing the psychtoolbox.

Related bug reports and patches do not seem to apply to 2015 version. What are the alternatives?

java.lang.NullPointerException at sun.reflect.UnsafeFieldAccessorImpl.ensureObj(UnsafeFieldAccessorImpl.java:54) at sun.reflect.UnsafeObjectFieldAccessorImpl.get(UnsafeObjectFieldAccessorImpl.java:36) at java.lang.reflect.Field.get(Field.java:379) at sun.lwawt.macosx.CAccessibility.getAccessibleRoleFor(CAccessibility.java:220) at sun.lwawt.macosx.CAccessibility$11.call(CAccessibility.java:235) at sun.lwawt.macosx.CAccessibility$11.call(CAccessibility.java:232) at sun.lwawt.macosx.LWCToolkit$CallableWrapper.run(LWCToolkit.java:526) at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:302) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:733) at java.awt.EventQueue.access$200(EventQueue.java:103) at java.awt.EventQueue$3.run(EventQueue.java:694) at java.awt.EventQueue$3.run(EventQueue.java:692) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87) at java.awt.EventQueue$4.run(EventQueue.java:708) at java.awt.EventQueue$4.run(EventQueue.java:706) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) at java.awt.EventQueue.dispatchEvent(EventQueue.java:705) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138) at java.awt.EventDispatchThread.run(EventDispatchThread.java:91) java.lang.NullPointerException at javax.swing.JList$AccessibleJList$AccessibleJListChild.getAccessibleValue(JList.java:3400) at sun.lwawt.macosx.CAccessibility$31.call(CAccessibility.java:542) at sun.lwawt.macosx.CAccessibility$31.call(CAccessibility.java:534) at sun.lwawt.macosx.LWCToolkit$CallableWrapper.run(LWCToolkit.java:526) at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:302) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:733) at java.awt.EventQueue.access$200(EventQueue.java:103) at java.awt.EventQueue$3.run(EventQueue.java:694) at java.awt.EventQueue$3.run(EventQueue.java:692) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87) at java.awt.EventQueue$4.run(EventQueue.java:708) at java.awt.EventQueue$4.run(EventQueue.java:706) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) at java.awt.EventQueue.dispatchEvent(EventQueue.java:705) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138) at java.awt.EventDispatchThread.run(EventDispatchThread.java:91) java.lang.NullPointerException at sun.reflect.UnsafeFieldAccessorImpl.ensureObj(UnsafeFieldAccessorImpl.java:54) at sun.reflect.UnsafeObjectFieldAccessorImpl.get(UnsafeObjectFieldAccessorImpl.java:36) at java.lang.reflect.Field.get(Field.java:379) at sun.lwawt.macosx.CAccessibility.getAccessibleRoleFor(CAccessibility.java:220) at sun.lwawt.macosx.CAccessibility$11.call(CAccessibility.java:235) at sun.lwawt.macosx.CAccessibility$11.call(CAccessibility.java:232) at sun.lwawt.macosx.LWCToolkit$CallableWrapper.run(LWCToolkit.java:526) at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:302) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:733) at java.awt.EventQueue.access$200(EventQueue.java:103) at java.awt.EventQueue$3.run(EventQueue.java:694) at java.awt.EventQueue$3.run(EventQueue.java:692) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87) at java.awt.EventQueue$4.run(EventQueue.java:708) at java.awt.EventQueue$4.run(EventQueue.java:706) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) at java.awt.EventQueue.dispatchEvent(EventQueue.java:705) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138) at java.awt.EventDispatchThread.run(EventDispatchThread.java:91) java.lang.NullPointerException at javax.swing.JList$AccessibleJList$AccessibleJListChild.getAccessibleValue(JList.java:3400) at sun.lwawt.macosx.CAccessibility$31.call(CAccessibility.java:542) at sun.lwawt.macosx.CAccessibility$31.call(CAccessibility.java:534) at sun.lwawt.macosx.LWCToolkit$CallableWrapper.run(LWCToolkit.java:526) at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:302) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:733) at java.awt.EventQueue.access$200(EventQueue.java:103) at java.awt.EventQueue$3.run(EventQueue.java:694) at java.awt.EventQueue$3.run(EventQueue.java:692) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87) at java.awt.EventQueue$4.run(EventQueue.java:708) at java.awt.EventQueue$4.run(EventQueue.java:706) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) at java.awt.EventQueue.dispatchEvent(EventQueue.java:705) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138) at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)

[John D'Errico]

I've not had any problems at all with Java. In fact, I don't recall the last time I had MATLAB or JAVA problems since I upped to El Capitan. Running OSX 10.11.6, with R2016a.

That might suggest upping your MATLAB release, or making sure the JAVA release is up to date and not corrupted. I might also suggest some disk utility checks, to make sure the problem is not disk corruption.