java.lang.IncompatibleClassChangeError: Class org.dmfs.jems.optional.decorators.Mapped does not implement the requested interface org.dmfs.jems.optional.Optional

[Armiron]

java.lang.IncompatibleClassChangeError: Class org.dmfs.jems.optional.decorators.Mapped does not implement the requested interface org.dmfs.jems.optional.Optional
at org.dmfs.oauth2.client.http.responsehandlers.TokenResponseHandler.handleResponse(TokenResponseHandler.java:56)
at org.dmfs.oauth2.client.http.responsehandlers.TokenResponseHandler.handleResponse(TokenResponseHandler.java:40)
at org.dmfs.httpessentials.httpurlconnection.PlainHttpUrlConnectionExecutor.execute(PlainHttpUrlConnectionExecutor.java:78)
at org.dmfs.httpessentials.executors.common.decorators.BottomBranded.execute(BottomBranded.java:54)
at org.dmfs.httpessentials.executors.common.decorators.BottomBranded.execute(BottomBranded.java:54)
at org.dmfs.httpessentials.httpurlconnection.HttpUrlConnectionExecutor.execute(HttpUrlConnectionExecutor.java:67)
at org.dmfs.httpessentials.executors.useragent.Branded.execute(Branded.java:53)
at org.dmfs.oauth2.client.BasicOAuth2AuthorizationProvider.accessToken(BasicOAuth2AuthorizationProvider.java:55)
at org.dmfs.oauth2.client.BasicOAuth2Client.accessToken(BasicOAuth2Client.java:71)
at org.dmfs.oauth2.client.grants.AuthorizationCodeGrant$AuthorizedAuthorizationCodeGrant.accessToken(AuthorizationCodeGrant.java:165)
at javaclient.OAuthClient.getToken(OAuthClient.java:91)
at javaclient.OAuthClient$3.changed(OAuthClient.java:136)
at javaclient.OAuthClient$3.changed(OAuthClient.java:122)
at com.sun.javafx.binding.ExpressionHelper$SingleChange.fireValueChangedEvent(ExpressionHelper.java:182)
at com.sun.javafx.binding.ExpressionHelper.fireValueChangedEvent(ExpressionHelper.java:81)
at javafx.beans.property.ReadOnlyStringPropertyBase.fireValueChangedEvent(ReadOnlyStringPropertyBase.java:72)
at javafx.beans.property.ReadOnlyStringWrapper.fireValueChangedEvent(ReadOnlyStringWrapper.java:103)
at javafx.beans.property.StringPropertyBase.markInvalid(StringPropertyBase.java:110)
at javafx.beans.property.StringPropertyBase.set(StringPropertyBase.java:144)
at javafx.scene.web.WebEngine.updateLocation(WebEngine.java:379)
at javafx.scene.web.WebEngine.access$2000(WebEngine.java:286)
at javafx.scene.web.WebEngine$LoadWorker.dispatchLoadEvent(WebEngine.java:1366)
at javafx.scene.web.WebEngine$LoadWorker.access$1200(WebEngine.java:1253)
at javafx.scene.web.WebEngine$PageLoadListener.dispatchLoadEvent(WebEngine.java:1240)
at com.sun.webkit.WebPage.fireLoadEvent(WebPage.java:2434)
at com.sun.webkit.WebPage.fwkFireLoadEvent(WebPage.java:2278)
at com.sun.webkit.network.URLLoader.twkWillSendRequest(Native Method)
at com.sun.webkit.network.URLLoader.notifyWillSendRequest(URLLoader.java:729)
at com.sun.webkit.network.URLLoader.lambda$willSendRequest$96(URLLoader.java:675)
at com.sun.javafx.application.PlatformImpl.lambda$null$173(PlatformImpl.java:295)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.application.PlatformImpl.lambda$runLater$174(PlatformImpl.java:294)
at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$148(WinApplication.java:191)
at java.lang.Thread.run(Thread.java:745)