What causes java.lang.InternalError: platform encoding not initialized ?

[Scott Palmer]

This is likely not the right place to ask this (sorry).. but I'm trying to
get info to write a bug report and want to make sure I'm not doing
something stupid first.

I've created a JRE image from JDK 17 with jlink.  I've made an
application image with jpackage.  I've moved the default location of the
runtime in the application image and modified the launcher .cfg file
accordingly by adding a line to the [Application] section

app.runtime=$APPDIR\..\my_own_folder\where_the_jre_is_deeper\jre

My application launches.  It shows a JavaFX GUI.  It does a bunch of stuff
that "works", but then one thread fails with this exception:

Exception in thread "Reader-BG-1" java.lang.InternalError: platform
encoding not initialized
        at java.base/java.net.Inet6AddressImpl.lookupAllHostAddr(Native
Method)
        at
java.base/java.net.InetAddress$PlatformNameService.lookupAllHostAddr(InetAddress.java:933)
        at
java.base/java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1519)
        at
java.base/java.net.InetAddress$NameServiceAddresses.get(InetAddress.java:852)
        at
java.base/java.net.InetAddress.getAllByName0(InetAddress.java:1509)
        at
java.base/java.net.InetAddress.getAllByName(InetAddress.java:1367)
        at
java.base/java.net.InetAddress.getAllByName(InetAddress.java:1301)
        at java.base/java.net.InetAddress.getByName(InetAddress.java:1251)
        at
java.base/java.net.InetSocketAddress.<init>(InetSocketAddress.java:229)
        at java.base/sun.net.NetworkClient.doConnect(NetworkClient.java:178)
        at
java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:498)
        at
java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:603)
        at
java.base/sun.net.www.protocol.https.HttpsClient.<init>(HttpsClient.java:266)
        at
java.base/sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:380)
        at
java.base/sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:189)
        at
java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1242)
        at
java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1128)
        at
java.base/sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:175)
        at
java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1665)
        at
java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1589)
        at
java.base/java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:529)
        at
java.base/sun.net.www.protocol.https.HttpsURLConnectionImpl.getResponseCode(HttpsURLConnectionImpl.java:308)

If I keep the runtime in $APPDIR\runtime, things don't fail in this way.

Smells like a bug in the app launcher to me.. but maybe it's in the runtime?

Any assistance would be appreciated (including telling me where I should go
to ask this, if this list isn't appropriate).

Thanks,

Scott