The following test failed in the JDK15 CI:

java/beans/XMLEncoder/Test4625418.java

Here's a snippet from the log file:

Test encoding: Cp933
Test encoding: Cp943
----------System.err:(14/830)----------
java.lang.Error: Cp943 - can't read properly
at Test4625418.test(Test4625418.java:392)
at Test4625418.main(Test4625418.java:359)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at com.sun.javatest.regtest.agent.MainWrapper$MainThread.run(MainWrapper.java:127)
at java.base/java.lang.Thread.run(Thread.java:832)

JavaTest Message: Test threw exception: java.lang.Error: Cp943 - can't read properly
JavaTest Message: shutting down test

STATUS:Failed.`main' threw exception: java.lang.Error: Cp943 - can't read properly
----------rerun:(35/4175)*----------

This failure is possibly related to this fix:

    JDK-8235834 IBM-943 charset encoder needs updating