【问题描述】
在IDEA中运行基于Maven构建Springboot项目时，报了如下的错误：
com.intellij.openapi.project.IndexNotReadyException: Please change caller according to com.intellij.openapi.project.IndexNotReadyException documentation
at com.intellij.openapi.project.IndexNotReadyException.create(IndexNotReadyException.java:77)
at com.intellij.util.indexing.FileBasedIndexImpl.handleDumbMode(FileBasedIndexImpl.java:777)
at com.intellij.util.indexing.FileBasedIndexImpl.ensureUpToDate(FileBasedIndexImpl.java:726)
at com.intellij.util.indexing.FileBasedIndexImpl.ensureUpToDate(FileBasedIndexImpl.java:709)
at com.intellij.psi.stubs.StubIndexImpl.doProcessStubs(StubIndexImpl.java:305)
at com.intellij.psi.stubs.StubIndexImpl.processElements(StubIndexImpl.java:281)
at com.intellij.psi.stubs.StubIndex.getElements(StubIndex.java:121)
at com.intellij.psi.stubs.StubIndex.getElements(StubIndex.java:109)
at com.intellij.psi.impl.java.stubs.index.JavaFullClassNameIndex.get(JavaFullClassNameIndex.java:47)
at com.intellij.psi.impl.file.impl.JavaFileManagerImpl.doFindClasses(JavaFileManagerImpl.java:88)
at com.intellij.psi.impl.file.impl.JavaFileManagerImpl.findClass(JavaFileManagerImpl.java:123)
at com.intellij.psi.impl.PsiElementFinderImpl.findClass(PsiElementFinderImpl.java:38)
at com.intellij.psi.impl.JavaPsiFacadeImpl.doFindClass(JavaPsiFacadeImpl.java:116)
at com.intellij.psi.impl.JavaPsiFacadeImpl.findClass(JavaPsiFacadeImpl.java:93)
at com.intellij.psi.util.InheritanceUtil.isInheritor(InheritanceUtil.java:94)
at com.intellij.psi.util.InheritanceUtil.isInheritor(InheritanceUtil.java:85)
at in.oneton.idea.spring.assistant.plugin.misc.PsiCustomUtil.isClassSameOrDescendantOf(PsiCustomUtil.java:287)
at in.oneton.idea.spring.assistant.plugin.misc.PsiCustomUtil.isMap(PsiCustomUtil.java:277)
at in.oneton.idea.spring.assistant.plugin.misc.PsiCustomUtil.getSuggestionNodeType(PsiCustomUtil.java:203)
at in.oneton.idea.spring.assistant.plugin.suggestion.metadata.MetadataNonPropertySuggestionNode.updateGroupType(MetadataNonPropertySuggestionNode.java:546)
at in.oneton.idea.spring.assistant.plugin.suggestion.metadata.MetadataNonPropertySuggestionNode.setGroup(MetadataNonPropertySuggestionNode.java:445)
at in.oneton.idea.spring.assistant.plugin.suggestion.service.SuggestionServiceImpl.addGroupsToIndex(SuggestionServiceImpl.java:578)
at in.oneton.idea.spring.assistant.plugin.suggestion.service.SuggestionServiceImpl.buildMetadataHierarchy(SuggestionServiceImpl.java:459)
at in.oneton.idea.spring.assistant.plugin.suggestion.service.SuggestionServiceImpl.processContainers(SuggestionServiceImpl.java:412)
at in.oneton.idea.spring.assistant.plugin.suggestion.service.SuggestionServiceImpl.reindexModule(SuggestionServiceImpl.java:449)
at in.oneton.idea.spring.assistant.plugin.suggestion.service.SuggestionServiceImpl.lambda$null$8(SuggestionServiceImpl.java:154)
at com.intellij.openapi.application.impl.ApplicationImpl.runReadAction(ApplicationImpl.java:945)
at in.oneton.idea.spring.assistant.plugin.suggestion.service.SuggestionServiceImpl.lambda$reindex$9(SuggestionServiceImpl.java:142)
at com.intellij.openapi.application.impl.ApplicationImpl$1.run(ApplicationImpl.java:311)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)【解决办法】
点击“File”-->“Invalidate Cache / Restart...”即可。
注：导致此问题的原因可能会有很多种，上述解决办法只是其中一种……
