After Upgrading from Jenkins 2.319 to Jenkins 2.320 yesterday (following the instructions to update all plugins both before and after the upgrade), all maven projects started to failed with below error.
Reverting to Jenkins 2.319 solved the issue. It's possible that this is not Jenkins core but a specific (maven) plugin missing a Guava upgrade, but since no updates are available as yet this is definitely a problem.

 > D:\ServApps\git\cmd\git.exe rev-list --no-walk a0269ab032c7e39a61878026a47e57101b708c50 # timeout=10 > D:\ServApps\git\cmd\git.exe rev-list --no-walk a0269ab032c7e39a61878026a47e57101b708c50 # timeout=10Posting build status of INPROGRESS to Bitbucket for commit id [58ab50ad71228eb727b30f32f951d00a294b4125] and ref 'refs/heads/feature/refactor-ajax-calls'Parsing POMsERROR: Processing failed due to a bug in the code. Please report this to the issue tracker (https://jenkins.io/redirect/report-an-issue).com.google.inject.CreationException: Unable to create injector, see the following errors:
1) Error injecting method, java.lang.NoSuchMethodError: com.google.common.base.Objects.toStringHelper(Ljava/lang/Class;)Lcom/google/common/base/Objects$ToStringHelper;  at org.eclipse.sisu.inject.DefaultBeanLocator.autoPublish(DefaultBeanLocator.java:197)  at org.codehaus.plexus.DefaultPlexusContainer$ContainerModule.configure(DefaultPlexusContainer.java:834) (via modules: org.eclipse.sisu.wire.WireModule -> org.codehaus.plexus.DefaultPlexusContainer$ContainerModule)
1 error at com.google.inject.internal.Errors.throwCreationExceptionIfErrorsExist(Errors.java:466) at com.google.inject.internal.InternalInjectorCreator.injectDynamically(InternalInjectorCreator.java:176) at com.google.inject.internal.InternalInjectorCreator.build(InternalInjectorCreator.java:110) at com.google.inject.Guice.createInjector(Guice.java:96) at com.google.inject.Guice.createInjector(Guice.java:73) at com.google.inject.Guice.createInjector(Guice.java:62) at org.codehaus.plexus.DefaultPlexusContainer.addPlexusInjector(DefaultPlexusContainer.java:481) at org.codehaus.plexus.DefaultPlexusContainer.<init>(DefaultPlexusContainer.java:206) at org.codehaus.plexus.DefaultPlexusContainer.<init>(DefaultPlexusContainer.java:168) at hudson.maven.MavenEmbedderUtils.buildPlexusContainer(MavenEmbedderUtils.java:166) at hudson.maven.MavenEmbedderUtils.buildPlexusContainer(MavenEmbedderUtils.java:159) at hudson.maven.MavenEmbedder.<init>(MavenEmbedder.java:110) at hudson.maven.MavenEmbedder.<init>(MavenEmbedder.java:137) at hudson.maven.MavenUtil.createEmbedder(MavenUtil.java:211) at hudson.maven.MavenModuleSetBuild$PomParser.invoke(MavenModuleSetBuild.java:1324) at hudson.maven.MavenModuleSetBuild$PomParser.invoke(MavenModuleSetBuild.java:1124) at hudson.FilePath.act(FilePath.java:1171) at hudson.FilePath.act(FilePath.java:1154) at hudson.maven.MavenModuleSetBuild$MavenModuleSetBuildExecution.parsePoms(MavenModuleSetBuild.java:985) at hudson.maven.MavenModuleSetBuild$MavenModuleSetBuildExecution.doRun(MavenModuleSetBuild.java:689) at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:520) at hudson.model.Run.execute(Run.java:1888) at hudson.maven.MavenModuleSetBuild.run(MavenModuleSetBuild.java:543) at hudson.model.ResourceController.execute(ResourceController.java:99) at hudson.model.Executor.run(Executor.java:432)Caused by: java.lang.NoSuchMethodError: com.google.common.base.Objects.toStringHelper(Ljava/lang/Class;)Lcom/google/common/base/Objects$ToStringHelper; at com.google.inject.internal.InstanceBindingImpl.toString(InstanceBindingImpl.java:92) at java.base/java.lang.String.valueOf(String.java:2951) at java.base/java.lang.StringBuilder.append(StringBuilder.java:168) at org.eclipse.sisu.inject.Logs.toString(Logs.java:205) at org.eclipse.sisu.inject.InjectorBindings.toString(InjectorBindings.java:129) at java.base/java.lang.String.valueOf(String.java:2951) at java.base/java.lang.StringBuilder.append(StringBuilder.java:168) at org.eclipse.sisu.inject.Logs.format(Logs.java:257) at org.eclipse.sisu.inject.Logs.trace(Logs.java:103) at org.eclipse.sisu.inject.DefaultBeanLocator.add(DefaultBeanLocator.java:91) at org.eclipse.sisu.inject.DefaultBeanLocator.staticAutoPublish(DefaultBeanLocator.java:203) at org.eclipse.sisu.inject.DefaultBeanLocator.autoPublish(DefaultBeanLocator.java:197) at org.eclipse.sisu.inject.DefaultBeanLocator$$FastClassByGuice$$5c8e0cfd.invoke(<generated>) at com.google.inject.internal.cglib.reflect.$FastMethod.invoke(FastMethod.java:53) at com.google.inject.internal.SingleMethodInjector$1.invoke(SingleMethodInjector.java:57) at com.google.inject.internal.SingleMethodInjector.inject(SingleMethodInjector.java:91) at com.google.inject.internal.MembersInjectorImpl.injectMembers(MembersInjectorImpl.java:132) at com.google.inject.internal.MembersInjectorImpl$1$1.call(MembersInjectorImpl.java:88) at com.google.inject.internal.ProvisionListenerStackCallback$Provision.provision(ProvisionListenerStackCallback.java:115) at org.eclipse.sisu.bean.BeanScheduler$CycleActivator.onProvision(BeanScheduler.java:230) at com.google.inject.internal.ProvisionListenerStackCallback$Provision.provision(ProvisionListenerStackCallback.java:126) at com.google.inject.internal.ProvisionListenerStackCallback.provision(ProvisionListenerStackCallback.java:68) at com.google.inject.internal.MembersInjectorImpl$1.call(MembersInjectorImpl.java:86) at com.google.inject.internal.MembersInjectorImpl$1.call(MembersInjectorImpl.java:80) at com.google.inject.internal.InjectorImpl.callInContext(InjectorImpl.java:1092) at com.google.inject.internal.MembersInjectorImpl.injectAndNotify(MembersInjectorImpl.java:80) at com.google.inject.internal.Initializer$InjectableReference.get(Initializer.java:174) at com.google.inject.internal.Initializer.injectAll(Initializer.java:108) at com.google.inject.internal.InternalInjectorCreator.injectDynamically(InternalInjectorCreator.java:174) ... 23 more