Maven errors with java 21

[nobody102]

upgrading project to JDK 21 and maven build fails on war plugin. Any thoughts?
.maven.plugin.DefaultMojosExecutionStrategy.execute (DefaultMojosExecutionStrategy.java:39)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:159)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:105)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:73)
at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build (SingleThreadedBuilder.java:53)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute (LifecycleStarter.java:118)
at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:261)
at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:173)
at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:101)
at org.apache.maven.cli.MavenCli.execute (MavenCli.java:906)
at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:283)
at org.apache.maven.cli.MavenCli.main (MavenCli.java:206)
at jdk.internal.reflect.DirectMethodHandleAccessor.invoke (DirectMethodHandleAccessor.java:103)
at java.lang.reflect.Method.invoke (Method.java:580)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:283)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:226)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:407)
at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:348)
Caused by: java.lang.ExceptionInInitializerError: Cannot access defaults field of Properties
at com.thoughtworks.xstream.converters.collections.PropertiesConverter. (PropertiesConverter.java:46)
at com.thoughtworks.xstream.XStream.setupConverters (XStream.java:647)
at com.thoughtworks.xstream.XStream. (XStream.java:445)
at com.thoughtworks.xstream.XStream. (XStream.java:385)
at com.thoughtworks.xstream.XStream. (XStream.java:342)
at org.apache.maven.plugin.war.util.WebappStructureSerializer. (WebappStructureSerializer.java:47)
at org.apache.maven.plugin.war.AbstractWarMojo. (AbstractWarMojo.java:316)
at org.apache.maven.plugin.war.WarMojo. (WarMojo.java:48)
at org.apache.maven.plugin.war.WarMojo$$FastClassByGuice$$232944262.GUICE$TRAMPOLINE ()
at org.apache.maven.plugin.war.WarMojo$$FastClassByGuice$$232944262.apply ()
at com.google.inject.internal.DefaultConstructionProxyFactory$FastClassProxy.newInstance (DefaultConstructionProxyFactory.java:82)
at com.google.inject.internal.ConstructorInjector.provision (ConstructorInjector.java:114)
at com.google.inject.internal.ConstructorInjector.access$000 (ConstructorInjector.java:33)
at com.google.inject.internal.ConstructorInjector$1.call (ConstructorInjector.java:98)
at com.google.inject.internal.ProvisionListenerStackCallback$Provision.provision (ProvisionListenerStackCallback.java:109)
at com.google.inject.internal.ProvisionListenerStackCallback$Provision.provision (ProvisionListenerStackCallback.java:124)
at com.google.inject.internal.ProvisionListenerStackCallback.provision (ProvisionListenerStackCallback.java:66)
at com.google.inject.internal.ConstructorInjector.construct (ConstructorInjector.java:93)
at com.google.inject.internal.ConstructorBindingImpl$Factory.get (ConstructorBindingImpl.java:300)
at com.google.inject.internal.InjectorImpl$1.get (InjectorImpl.java:1101)
at com.google.inject.internal.InjectorImpl.getInstance (InjectorImpl.java:1139)
at org.eclipse.sisu.space.AbstractDeferredClass.get (AbstractDeferredClass.java:48)
at com.google.inject.internal.ProviderInternalFactory.provision (ProviderInternalFactory.java:86)
at com.google.inject.internal.InternalFactoryToInitializableAdapter.provision (InternalFactoryToInitializableAdapter.java:57)
at com.google.inject.internal.ProviderInternalFactory$1.call (ProviderInternalFactory.java:67)
at com.google.inject.internal.ProvisionListenerStackCallback$Provision.provision (ProvisionListenerStackCallback.java:109)
at com.google.inject.internal.ProvisionListenerStackCallback$Provision.provision (ProvisionListenerStackCallback.java:124)
at com.google.inject.internal.ProvisionListenerStackCallback.provision (ProvisionListenerStackCallback.java:66)
at com.google.inject.internal.ProviderInternalFactory.circularGet (ProviderInternalFactory.java:62)
at com.google.inject.internal.InternalFactoryToInitializableAdapter.get (InternalFactoryToInitializableAdapter.java:47)
at com.google.inject.internal.InjectorImpl$1.get (InjectorImpl.java:1101)
at org.eclipse.sisu.inject.Guice4$1.get (Guice4.java:162)
at org.eclipse.sisu.inject.LazyBeanEntry.getValue (LazyBeanEntry.java:81)
at org.eclipse.sisu.plexus.LazyPlexusBean.getValue (LazyPlexusBean.java:51)
at org.codehaus.plexus.DefaultPlexusContainer.lookup (DefaultPlexusContainer.java:263)
at org.codehaus.plexus.DefaultPlexusContainer.lookup (DefaultPlexusContainer.java:255)
at org.apache.maven.plugin.internal.DefaultMavenPluginManager.getConfiguredMojo (DefaultMavenPluginManager.java:491)
at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo (DefaultBuildPluginManager.java:114)
at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute2 (MojoExecutor.java:328)
at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute (MojoExecutor.java:316)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:212)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:174)
at org.apache.maven.lifecycle.internal.MojoExecutor.access$000 (MojoExecutor.java:75)
at org.apache.maven.lifecycle.internal.MojoExecutor$1.run (MojoExecutor.java:162)
at org.apache.maven.plugin.DefaultMojosExecutionStrategy.execute (DefaultMojosExecutionStrategy.java:39)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:159)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:105)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:73)
at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build (SingleThreadedBuilder.java:53)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute (LifecycleStarter.java:118)
at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:261)
at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:173)
at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:101)
at org.apache.maven.cli.MavenCli.execute (MavenCli.java:906)
at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:283)
at org.apache.maven.cli.MavenCli.main (MavenCli.java:206)
at jdk.internal.reflect.DirectMethodHandleAccessor.invoke (DirectMethodHandleAccessor.java:103)
at java.lang.reflect.Method.invoke (Method.java:580)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:283)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:226)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:407)
at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:348)

[joehni]

You will have to run Maven with the JVM option "--add-opens=java.base/java.util=ALL-UNNAMED".