Regression in DirectByteBufferDeallocator using Unsafe with Java 11

The same code is working absolutely fine with Java 10.0.2 and Java 10 modules.

14:18:44.417 [XNIO-1 task-13] ERROR io.undertow.request - UT005071: Undertow request failed HttpServerExchange{ POST /callback request

{Accept=[text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8], Accept-Language=[en-US,en;q=0.9,ru;q=0.8], Cache-Control=[max-age=0], Accept-Encoding=[gzip, deflate, br], DNT=[1], Origin=[https://login.microsoftonline.com], User-Agent=[Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.102 Safari/537.36], Connection=[keep-alive], Content-Length=[1486], Content-Type=[application/x-www-form-urlencoded], Upgrade-Insecure-Requests=[1], Host=[localhost:8443]}

response {Connection=[keep-alive], Content-Length=[0], Date=[Sun, 18 Nov 2018 19:18:44 GMT]}}
java.lang.ExceptionInInitializerError: null
at undertow.core@2.0.15.Final/io.undertow.server.DefaultByteBufferPool.queueIfUnderMax(DefaultByteBufferPool.java:209)
at undertow.core@2.0.15.Final/io.undertow.server.DefaultByteBufferPool.freeInternal(DefaultByteBufferPool.java:201)
at undertow.core@2.0.15.Final/io.undertow.server.DefaultByteBufferPool.access$200(DefaultByteBufferPool.java:41)
at undertow.core@2.0.15.Final/io.undertow.server.DefaultByteBufferPool$DefaultPooledBuffer.close(DefaultByteBufferPool.java:271)
at undertow.core@2.0.15.Final/io.undertow.protocols.ssl.SslConduit.doUnwrap(SslConduit.java:843)
at undertow.core@2.0.15.Final/io.undertow.protocols.ssl.SslConduit.read(SslConduit.java:567)
at xnio.api@3.3.8.Final/org.xnio.conduits.AbstractStreamSourceConduit.read(AbstractStreamSourceConduit.java:51)
at undertow.core@2.0.15.Final/io.undertow.conduits.ReadDataStreamSourceConduit.read(ReadDataStreamSourceConduit.java:67)
at undertow.core@2.0.15.Final/io.undertow.conduits.FixedLengthStreamSourceConduit.read(FixedLengthStreamSourceConduit.java:244)
at xnio.api@3.3.8.Final/org.xnio.conduits.ConduitStreamSourceChannel.read(ConduitStreamSourceChannel.java:127)
at undertow.core@2.0.15.Final/io.undertow.channels.DetachableStreamSourceChannel.read(DetachableStreamSourceChannel.java:209)
at undertow.core@2.0.15.Final/io.undertow.server.HttpServerExchange$ReadDispatchChannel.read(HttpServerExchange.java:2341)
at undertow.core@2.0.15.Final/io.undertow.server.handlers.form.FormEncodedDataDefinition$FormEncodedDataParser.doParse(FormEncodedDataDefinition.java:134)
at undertow.core@2.0.15.Final/io.undertow.server.handlers.form.FormEncodedDataDefinition$FormEncodedDataParser.parseBlocking(FormEncodedDataDefinition.java:252)
at auth.server/auth.server.auth.OIDCCallbackHandler.handleRequest(OIDCCallbackHandler.java:52)
at undertow.core@2.0.15.Final/io.undertow.server.Connectors.executeRootHandler(Connectors.java:360)
at undertow.core@2.0.15.Final/io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:830)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: java.lang.RuntimeException: JDK did not allow accessing unsafe
at undertow.core@2.0.15.Final/io.undertow.server.DirectByteBufferDeallocator.getUnsafe0(DirectByteBufferDeallocator.java:106)
at undertow.core@2.0.15.Final/io.undertow.server.DirectByteBufferDeallocator.getUnsafe(DirectByteBufferDeallocator.java:97)
at undertow.core@2.0.15.Final/io.undertow.server.DirectByteBufferDeallocator.<clinit>(DirectByteBufferDeallocator.java:46)
... 20 common frames omitted
Caused by: java.lang.NoClassDefFoundError: sun/misc/Unsafe
at undertow.core@2.0.15.Final/io.undertow.server.DirectByteBufferDeallocator.getUnsafe0(DirectByteBufferDeallocator.java:102)
... 22 common frames omitted
Caused by: java.lang.ClassNotFoundException: sun.misc.Unsafe
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
... 23 common frames omitted