貌似解决了问题，maven 已经开始导入了.
原因：idea2019与maven3.6版本不兼容问题，解决办法，要么升级idea，要么降级maven。
原来用的3.6.2，现在换成了3.3.9
哪里出了问题？
Unable to import maven project: See logs for details
logs:
Exit code 1
2020-10-16 22:05:46,758 [ 489685] INFO - ution.rmi.RemoteProcessSupport - Terminating: 17444/Maven3ServerImpl6e8af776
2020-10-16 22:05:46,994 [ 489921] INFO - stubs.SerializationManagerImpl - START StubSerializationManager SHUTDOWN
2020-10-16 22:05:46,994 [ 489921] INFO - stubs.SerializationManagerImpl - END StubSerializationManager SHUTDOWN
2020-10-16 22:05:46,995 [ 489922] INFO - il.indexing.FileBasedIndexImpl - START INDEX SHUTDOWN
2020-10-16 22:05:47,019 [ 489946] INFO - il.indexing.FileBasedIndexImpl - END INDEX SHUTDOWN
2020-10-16 22:05:47,020 [ 489947] INFO - org.jetbrains.io.BuiltInServer - web server stopped
2020-10-16 22:05:47,038 [ 489965] INFO - Types.impl.FileTypeManagerImpl - FileTypeManager: 0 auto-detected files
Elapsed time on auto-detect: 0 ms
2020-10-16 22:05:47,046 [ 489973] INFO - pl.local.NativeFileWatcherImpl - Watcher terminated with exit code 0
2020-10-16 22:05:47,050 [ 489977] INFO - newvfs.persistent.PersistentFS - VFS dispose started
2020-10-16 22:05:47,069 [ 489996] INFO - newvfs.persistent.PersistentFS - VFS dispose completed
2020-10-16 22:05:47,076 [ 490003] INFO - #com.intellij.idea.Main - ------------------------------------------------------ IDE SHUTDOWN ------------------------------------------------------
2020-10-16 22:05:47,083 [ 490010] INFO - org.jetbrains.io.BuiltInServer - web server stopped
2020-10-16 22:05:53,475 [ 0] INFO - #com.intellij.idea.Main - ------------------------------------------------------ IDE STARTED ------------------------------------------------------
2020-10-16 22:05:53,496 [ 21] INFO - #com.intellij.idea.Main - IDE: IntelliJ IDEA (build #IU-182.4505.22, 18 Sep 2018 19:53)
2020-10-16 22:05:53,496 [ 21] INFO - #com.intellij.idea.Main - OS: Windows 10 (10.0, amd64)
2020-10-16 22:05:53,496 [ 21] INFO - #com.intellij.idea.Main - JRE: 1.8.0_152-release-1248-b8 (JetBrains s.r.o)
2020-10-16 22:05:53,496 [ 21] INFO - #com.intellij.idea.Main - JVM: 25.152-b8 (OpenJDK 64-Bit Server VM)
2020-10-16 22:05:53,499 [ 24] INFO - #com.intellij.idea.Main - JVM Args: -Xms128m -Xmx750m -XX:ReservedCodeCacheSize=240m -XX:+UseConcMarkSweepGC -XX:SoftRefLRUPolicyMSPerMB=50 -ea -Dsun.io.useCanonCaches=false -Djava.net.preferIPv4Stack=true -Djdk.http.auth.tunneling.disabledSchemes="" -XX:+HeapDumpOnOutOfMemoryError -XX:-OmitStackTraceInFastThrow -Djb.vmOptionsFile=D:SoftIntelliJ IDEA 2018.2.4inidea64.exe.vmoptions -Didea.jre.check=true -Dide.native.launcher=true -Didea.paths.selector=IntelliJIdea2018.2 -XX:ErrorFile=C:Users
icaijava_error_in_idea_%p.log -XX:HeapDumpPath=C:Users
icaijava_error_in_idea.hprof
2020-10-16 22:05:53,499 [ 24] INFO - #com.intellij.idea.Main - ext: D:SoftIntelliJ IDEA 2018.2.4jre64libext: [access-bridge-64.jar, cldrdata.jar, dnsns.jar, jaccess.jar, jfxrt.jar, localedata.jar, meta-index, nashorn.jar, sunec.jar, sunjce_provider.jar, sunmscapi.jar, sunpkcs11.jar, zipfs.jar]
2020-10-16 22:05:53,499 [ 24] INFO - #com.intellij.idea.Main - charsets: JNU=GBK file=GBK
2020-10-16 22:05:53,569 [ 94] INFO - #com.intellij.idea.Main - JNA library (64-bit) loaded in 69 ms
2020-10-16 22:05:53,571 [ 96] INFO - penapi.util.io.win32.IdeaWin32 - Native filesystem for Windows is operational
2020-10-16 22:05:53,822 [ 347] INFO - #com.intellij.util.ui.JBUI - User scale factor: 1.0
2020-10-16 22:05:55,009 [ 1534] INFO - .intellij.idea.IdeaApplication - CPU cores: 12; ForkJoinPool.commonPool: java.util.concurrent.ForkJoinPool@65ab102a[Running, parallelism = 11, size = 0, active = 0, running = 0, steals = 0, tasks = 0, submissions = 0]; factory: com.intellij.concurrency.IdeaForkJoinWorkerThreadFactory@d2746aa
2020-10-16 22:05:55,031 [ 1556] INFO - #com.intellij.util.ui.JBUI - System scale factor: 1.25 (JRE-managed HiDPI)
2020-10-16 22:05:55,915 [ 2440] INFO - llij.ide.plugins.PluginManager - 131 plugins initialized in 675 ms
2020-10-16 22:05:55,916 [ 2441] INFO - llij.ide.plugins.PluginManager - Loaded bundled plugins: ASP (0.1), Android Support (10.3.1.2), AngularJS (182.4505.22), Ant Support (1.0), Application Servers View (0.2.0), AspectJ Support (1.2), Bytecode Viewer (0.1), CFML Support (3.53), CSS Support (182.4505.22), CVS Integration (11), Cloud Foundry integration (1.0), CloudBees integration (1.0), CoffeeScript (182.4505.22), Copyright (8.1), Coverage (182.4505.22), Cucumber for Groovy (182.4505.22), Cucumber for Java (182.4505.22), DSM Analysis (1.0.0), Database Tools and SQL (182.4505.22), Eclipse Integration (3.0), EditorConfig (182.4505.22), Emma (182.4505.22), Flash/Flex Support (182.4505.22), FreeMarker support (1.0), GWT Support (1.0), Geronimo Integration (1.0), Gherkin (999.999), Git Integration (8.1), GitHub (182.4505.22), GlassFish Integration (1.0), Google App Engine Integration (1.1.4), Gradle (182.4505.22), Grails (9.0), Groovy (9.0), Guice (8.0), HTML Tools (2.0), HTTP Client (182.4505.22), Haml (182.4505.22), Heroku integration (182.4505.22), Hibernate Support (1.0), I18n for Java (182.4505.22), IDE Settings Sync (182.4505.22), IDEA CORE (182.4505.22), IntelliLang (8.0), J2ME (1.0), JBoss Arquillian Support (1.0), JBoss Drools Support (1.0), JBoss Frameworks Base Support (1.0), JBoss Integration (1.0), JBoss Seam Pageflow Support (1.0), JBoss Seam Pages Support (1.0), JBoss Seam Support (1.0), JBoss jBPM (2.0.0), JSR45 Integration (1.0), JUnit (1.0), Java Bytecode Decompiler (182.4505.22), Java EE: Batch Applications (1.0), Java EE: Bean Validation Support (1.1), Java EE: Contexts and Dependency Injection (1.1), Java EE: EJB, JPA, Servlets (1.0), Java EE: JMS, JSON Processing, Concurrency, Transaction (1.0), Java EE: Java Server Faces (2.2.X.), Java EE: RESTful Web Services (JAX-RS) (1.0), Java EE: Web Services (JAX-WS) (1.9), Java EE: WebSockets (1.0), Java Server Pages (JSP) Integration (1.0), Java Stream Debugger (182.4505.22), JavaFX (1.0), JavaScript Debugger (1.0), JavaScript Intention Power Pack (0.9.4), JavaScript Support (1.0), Jetty Integration (1.0), Kotlin (1.2.51-release-IJ2018.2-1), Less support (182.4505.22), Markdown support (182.4505.22), Maven Integration (182.4505.22), Maven Integration Extension (182.4505.22), Mercurial Integration (10.0), OpenShift integration (1.0), Osmorc (1.4.12), Perforce Integration (2.0), Persistence Frameworks Support (1.0), Playframework Support (1.0), Plugin DevKit (1.0), Properties Support (182.4505.22), Reactor framework support (1.0), Refactor-X (2.01), Remote Hosts Access (0.1), Resin Integration (8.1), SSH Remote Run (0.1), Sass support (182.4505.22), Settings Repository (182.4505.22), Smali Support (1.0), Spring AOP/@AspectJ (1.0), Spring Batch (1.0), Spring Boot (1.0), Spring Data (1.0), Spring Integration Patterns (1.0), Spring MVC (1.0), Spring OSGi (1.0), Spring Security (1.0), Spring Support (1.0), Spring Web Flow (1.0), Spring Web Services (1.0), Spring WebSocket (1.0), Spy-js (182.4505.22), Struts 1.x (2.0), Struts 2 (1.0), Stylus support (999.999), Subversion Integration (1.1), TFS Integration (999.999), Tapestry support (1.0), Task Management (1.0), Terminal (0.1), TestNG-J (8.0), Thymeleaf (1.0), Time Tracking (1.0), Tomcat and TomEE Integration (1.0), UI Designer (182.4505.22), UML Support (1.0), Vaadin Support (1.0), Velocity support (1.0), W3C Validators (2.0), WebLogic Integration (1.0), WebSphere Integration (1.0), XPathView + XSLT Support (4), XSLT-Debugger (1.4), YAML (182.4505.22), ZKM-Unscramble (1.0), dmServer Support (0.9.5), tslint (182.4505.22)
2020-10-16 22:05:57,135 [ 3660] INFO - cloudConfig.CloudConfigManager - === Exit: JBA_NOT_FOUND ===
2020-10-16 22:05:57,188 [ 3713] INFO - ellij.util.io.PagedFileStorage - lower=100; upper=500; buffer=10; max=705
2020-10-16 22:05:57,235 [ 3760] INFO - pl.local.NativeFileWatcherImpl - Starting file watcher: D:SoftIntelliJ IDEA 2018.2.4infsnotifier64.exe
2020-10-16 22:05:57,258 [ 3783] INFO - pl.local.NativeFileWatcherImpl - Native file watcher is operational.
2020-10-16 22:05:57,426 [ 3951] INFO - tellij.openapi.util.IconLoader - replace '/nodes/newFolder.png' with 'AllIcons.Nodes.Folder'
2020-10-16 22:05:58,324 [ 4849] INFO - til.net.ssl.CertificateManager - Default SSL context initialized
2020-10-16 22:05:58,351 [ 4876] INFO - rains.ide.BuiltInServerManager - built-in server started, port 63342
2020-10-16 22:05:58,408 [ 4933] INFO - gs.impl.UpdateCheckerComponent - channel: release
2020-10-16 22:05:58,563 [ 5088] INFO - j.ide.ui.OptionsTopHitProvider - 267 ms spent to cache options in application
2020-10-16 22:05:58,563 [ 5088] INFO - .openapi.application.Preloader - com.intellij.ide.ui.OptionsTopHitProvider$Activity took 267 ms
2020-10-16 22:05:58,587 [ 5112] INFO - il.indexing.FileBasedIndexImpl - Index exts enumerated:138, number of extensions:77
2020-10-16 22:05:58,666 [ 5191] INFO - il.indexing.FileBasedIndexImpl - Index scheduled:78
2020-10-16 22:05:58,711 [ 5236] INFO - tellij.psi.stubs.StubIndexImpl - All stub exts enumerated:39, number of extensions:111
2020-10-16 22:05:58,712 [ 5237] INFO - tellij.psi.stubs.StubIndexImpl - stub exts update scheduled:0
2020-10-16 22:05:59,314 [ 5839] INFO - plication.impl.ApplicationImpl - 102 application components initialized in 4076ms
2020-10-16 22:05:59,328 [ 5853] INFO - .intellij.idea.IdeaApplication - App initialization took 7680 ms
2020-10-16 22:05:59,685 [ 6210] INFO - m.intellij.ui.mac.touchbar.NST - OS doesn't support touchbar, skip nst loading
2020-10-16 22:06:00,551 [ 7076] INFO - pl$FileIndexDataInitialization - Initialization done:1885
2020-10-16 22:06:00,629 [ 7154] INFO - com.intellij.ide.ui.UISettings - Loaded: fontSize=12, fontScale=1.0; restored: fontSize=12, fontScale=1.0
2020-10-16 22:06:00,631 [ 7156] INFO - com.intellij.ide.ui.UISettings - Loaded: fontSize=14, fontScale=1.0; restored: fontSize=14, fontScale=1.0
2020-10-16 22:06:00,950 [ 7475] INFO - CompilerWorkspaceConfiguration - Available processors: 12
2020-10-16 22:06:01,102 [ 7627] INFO - exImpl$StubIndexInitialization - Initialization done:550
2020-10-16 22:06:01,170 [ 7695] INFO - .openapi.application.Preloader - com.intellij.openapi.actionSystem.impl.ActionPreloader took 2605 ms
2020-10-16 22:06:01,561 [ 8086] INFO - ellij.project.impl.ProjectImpl - 189 project components initialized in 1566 ms
2020-10-16 22:06:01,918 [ 8443] INFO - le.impl.ModuleManagerComponent - 2 module(s) loaded in 356 ms
2020-10-16 22:06:02,179 [ 8704] INFO - j.ide.script.IdeStartupScripts - 0 startup script(s) found
2020-10-16 22:06:02,394 [ 8919] INFO - om.intellij.util.ProfilingUtil - Profiling agent is not enabled. Add -agentlib:yjpagent to idea.vmoptions if necessary to profile IDEA.
2020-10-16 22:06:02,654 [ 9179] INFO - .openapi.application.Preloader - com.intellij.ide.ui.search.SearchableOptionPreloader took 1482 ms
2020-10-16 22:06:02,978 [ 9503] INFO - .openapi.application.Preloader - com.intellij.codeInsight.completion.CompletionPreloader took 323 ms
2020-10-16 22:06:02,985 [ 9510] INFO - .openapi.application.Preloader - com.intellij.ide.actions.GotoClassPresentationUpdater took 5 ms
2020-10-16 22:06:03,151 [ 9676] INFO - ellij.project.impl.ProjectImpl - 20 project components initialized in 23 ms
2020-10-16 22:06:03,584 [ 10109] INFO - .diagnostic.PerformanceWatcher - Pushing properties took 460ms; general responsiveness: ok; EDT responsiveness: ok
2020-10-16 22:06:04,642 [ 11167]
