What does this error mean in INTELLIJ IDEA?

Question

IntelliJ IDEA

Good
, it actually hangs all the time

Write access is allowed from write-safe contexts only. Please ensure you're using invokeLater/invokeAndWait with a correct modality state (not "any"). See TransactionGuard documentation for details.
  current modality=ModalityState.NON_MODAL
  known modalities={ModalityState.NON_MODAL=true, ModalityState:com.intellij.openapi.ui.impl.DialogWrapperPeerImpl$MyDialog[dialog2,640,269,640x502,invalid,hidden,layout=java.awt.BorderLayout,APPLICATION_MODAL,title=Select Deployment Target,defaultCloseOperation=DO_NOTHING_ON_CLOSE,rootPane=,rootPaneCheckingEnabled=true]=true, ModalityState:com.intellij.openapi.ui.impl.DialogWrapperPeerImpl$MyDialog[dialog1,640,269,640x502,invalid,hidden,layout=java.awt.BorderLayout,APPLICATION_MODAL,title=Select Deployment Target,defaultCloseOperation=DO_NOTHING_ON_CLOSE,rootPane=,rootPaneCheckingEnabled=true]=true, ModalityState:com.intellij.openapi.ui.impl.DialogWrapperPeerImpl$MyDialog[dialog0,640,269,640x502,invalid,hidden,layout=java.awt.BorderLayout,APPLICATION_MODAL,title=Select Deployment Target,defaultCloseOperation=DO_NOTHING_ON_CLOSE,rootPane=,rootPaneCheckingEnabled=true]=true}
java.lang.Throwable
  at com.intellij.openapi.diagnostic.Logger.error(Logger.java:132)
  at com.intellij.openapi.application.TransactionGuardImpl.assertWriteActionAllowed(TransactionGuardImpl.java:246)
  at com.intellij.openapi.fileEditor.impl.FileDocumentManagerImpl.saveAllDocuments(FileDocumentManagerImpl.java:296)
  at com.intellij.openapi.fileEditor.impl.FileDocumentManagerImpl.saveAllDocuments(FileDocumentManagerImpl.java:288)
  at com.android.tools.idea.gradle.invoker.GradleInvoker.lambda$saveAllFilesSafely$0(GradleInvoker.java:321)
  at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:301)
  at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:756)
  at java.awt.EventQueue.access$500(EventQueue.java:97)
  at java.awt.EventQueue$3.run(EventQueue.java:709)
  at java.awt.EventQueue$3.run(EventQueue.java:703)
  at java.security.AccessController.doPrivileged(Native Method)
  at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
  at java.awt.EventQueue.dispatchEvent(EventQueue.java:726)
  at com.intellij.ide.IdeEventQueue.c(IdeEventQueue.java:843)
  at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.java:679)
  at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.java:391)
  at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
  at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
  at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
  at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
  at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
  at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)


java.lang.Throwable
  at com.intellij.openapi.diagnostic.Logger.error(Logger.java:132)
  at com.intellij.openapi.application.TransactionGuardImpl.assertWriteActionAllowed(TransactionGuardImpl.java:246)
  at com.intellij.openapi.fileEditor.impl.FileDocumentManagerImpl.saveAllDocuments(FileDocumentManagerImpl.java:296)
  at com.intellij.openapi.fileEditor.impl.FileDocumentManagerImpl.saveAllDocuments(FileDocumentManagerImpl.java:288)
  at com.android.tools.idea.gradle.invoker.GradleInvoker.lambda$saveAllFilesSafely$0(GradleInvoker.java:321)
  at com.intellij.util.ui.UIUtil.invokeAndWaitIfNeeded(UIUtil.java:2510)
  at com.android.tools.idea.gradle.invoker.GradleInvoker.saveAllFilesSafely(GradleInvoker.java:321)
  at com.android.tools.idea.gradle.invoker.GradleInvoker.executeTasks(GradleInvoker.java:304)
  at com.android.tools.idea.gradle.invoker.GradleInvoker.executeTasks(GradleInvoker.java:258)
  at com.android.tools.idea.gradle.invoker.GradleInvoker.executeTasks(GradleInvoker.java:232)
  at com.android.tools.idea.gradle.run.GradleTaskRunner$1.lambda$run$0(GradleTaskRunner.java:74)
  at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:301)
  at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:756)
  at java.awt.EventQueue.access$500(EventQueue.java:97)
  at java.awt.EventQueue$3.run(EventQueue.java:709)
  at java.awt.EventQueue$3.run(EventQueue.java:703)
  at java.security.AccessController.doPrivileged(Native Method)
  at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
  at java.awt.EventQueue.dispatchEvent(EventQueue.java:726)
  at com.intellij.ide.IdeEventQueue.c(IdeEventQueue.java:843)
  at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.java:679)
  at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.java:391)
  at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
  at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
  at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
  at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
  at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
  at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

Answer 1

https://www.google.com.ua/search?q=idea+Write+acce...
https://github.com/mplushnikov/lombok-intellij-plu...

Usually, but not always, this occurs when I open a second project after my main project is open.
All of our projects are java 8, maven projects making use of lombok (ie in smal project, I count 68 lombok imports split across 26 classes.)