新建第一个springboot项目，按照教程好像是旗舰版(这个不确定了，反正是只有一个才有它的)有Spring Initializr，然后一步步新建成功，看教程人家都是直接跑起来的，我的是先加载依赖，加了好久，然后我就乱点，不加载了。（我之前用过springboot,所以知道src 下有一个application.java[一般这个文件名前还有一个你的项目名，反正就是这么回事]，运行它，启动这个项目，我就想开始运行它）
但是配置文件中根本没有Spring Boot，我的pom.xml也不报错。当时并不知道是Maven的事，又重新重建了一下，发现是maven的问题，我看了一眼我的maven也是正常的，
又试了网上的这种办法，发现也行不通，而且每次加载的时候都特别慢，
又先试了右边的install，也不行，最开始控制台报错还是一堆乱码，后来修改左边的这个红色圈的地方 值变为:-Dfile.encoding=GB2312，就不乱码了， 让我下载一堆jar包和不知道是什么的文件，我下载了也不好使，后来查看的log如下，按照网的一个说法，删除c盘中的C:\Users\你的电脑名\.m2，整个文件一删除就好了。虽然我后面的错误和他们的不一样，但是这么做确实好使，困扰了我一下午的问题，差点就退劝了，但是坚持下去，我们要相信自己一定可以的
2021-01-22 16:11:04,490 [1584308] ERROR - #org.jetbrains.idea.maven - Cannot reconnect.
java.lang.RuntimeException: Cannot reconnect.
at org.jetbrains.idea.maven.server.RemoteObjectWrapper.perform(RemoteObjectWrapper.java:82)
at org.jetbrains.idea.maven.server.MavenServerManager.applyProfiles(MavenServerManager.java:531)
at org.jetbrains.idea.maven.project.MavenProjectReader.applyProfiles(MavenProjectReader.java:399)
at org.jetbrains.idea.maven.project.MavenProjectReader.doReadProjectModel(MavenProjectReader.java:108)
at org.jetbrains.idea.maven.project.MavenProjectReader.access$300(MavenProjectReader.java:51)
at org.jetbrains.idea.maven.project.MavenProjectReader$1.doProcessParent(MavenProjectReader.java:453)
at org.jetbrains.idea.maven.project.MavenProjectReader$1.doProcessParent(MavenProjectReader.java:429)
at org.jetbrains.idea.maven.project.MavenParentProjectFileProcessor.processRepositoryParent(MavenParentProjectFileProcessor.java:84)
at org.jetbrains.idea.maven.project.MavenParentProjectFileProcessor.process(MavenParentProjectFileProcessor.java:62)
at org.jetbrains.idea.maven.project.MavenProjectReader.resolveInheritance(MavenProjectReader.java:456)
at org.jetbrains.idea.maven.project.MavenProjectReader.doReadProjectModel(MavenProjectReader.java:105)
at org.jetbrains.idea.maven.project.MavenProjectReader.access$300(MavenProjectReader.java:51)
at org.jetbrains.idea.maven.project.MavenProjectReader$1.doProcessParent(MavenProjectReader.java:453)
at org.jetbrains.idea.maven.project.MavenProjectReader$1.doProcessParent(MavenProjectReader.java:429)
at org.jetbrains.idea.maven.project.MavenParentProjectFileProcessor.processRepositoryParent(MavenParentProjectFileProcessor.java:84)
at org.jetbrains.idea.maven.project.MavenParentProjectFileProcessor.process(MavenParentProjectFileProcessor.java:62)
at org.jetbrains.idea.maven.project.MavenProjectReader.resolveInheritance(MavenProjectReader.java:456)
at org.jetbrains.idea.maven.project.MavenProjectReader.doReadProjectModel(MavenProjectReader.java:105)
at org.jetbrains.idea.maven.project.MavenProjectReader.readProject(MavenProjectReader.java:67)
at org.jetbrains.idea.maven.project.MavenProjectReader.lambda$resolveProject$0(MavenProjectReader.java:531)
at com.intellij.util.containers.ContainerUtilRt.mapNotNull(ContainerUtilRt.java:395)
at com.intellij.util.containers.ContainerUtil.mapNotNull(ContainerUtil.java:1979)
at org.jetbrains.idea.maven.project.MavenProjectReader.resolveProject(MavenProjectReader.java:530)
at org.jetbrains.idea.maven.project.MavenProjectsTree.doResolve(MavenProjectsTree.java:1293)
at org.jetbrains.idea.maven.project.MavenProjectsTree.resolve(MavenProjectsTree.java:1265)
at org.jetbrains.idea.maven.project.MavenProjectsProcessorResolvingTask.perform(MavenProjectsProcessorResolvingTask.java:45)
at org.jetbrains.idea.maven.project.MavenProjectsProcessor.doProcessPendingTasks(MavenProjectsProcessor.java:134)
at org.jetbrains.idea.maven.project.MavenProjectsProcessor.access$000(MavenProjectsProcessor.java:32)
at org.jetbrains.idea.maven.project.MavenProjectsProcessor$2.run(MavenProjectsProcessor.java:109)
at org.jetbrains.idea.maven.utils.MavenUtil.lambda$runInBackground$5(MavenUtil.java:451)
at com.intellij.openapi.application.impl.ApplicationImpl$1.run(ApplicationImpl.java:314)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.rmi.UnmarshalException: Error unmarshaling return header; nested exception is:
java.net.SocketException: Connection reset
at sun.rmi.transport.StreamRemoteCall.executeCall(StreamRemoteCall.java:229)
at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:162)
at java.rmi.server.RemoteObjectInvocationHandler.invokeRemoteMethod(RemoteObjectInvocationHandler.java:227)
at java.rmi.server.RemoteObjectInvocationHandler.invoke(RemoteObjectInvocationHandler.java:179)
at com.sun.proxy.$Proxy132.applyProfiles(Unknown Source)
at sun.reflect.GeneratedMethodAccessor658.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.intellij.execution.rmi.RemoteUtil.invokeRemote(RemoteUtil.java:179)
at com.intellij.execution.rmi.RemoteUtil.access$300(RemoteUtil.java:39)
at com.intellij.execution.rmi.RemoteUtil$2$1$1.compute(RemoteUtil.java:160)
at com.intellij.openapi.util.ClassLoaderUtil.runWithClassLoader(ClassLoaderUtil.java:66)
at com.intellij.execution.rmi.RemoteUtil.executeWithClassLoader(RemoteUtil.java:231)
at com.intellij.execution.rmi.RemoteUtil$2$1.invoke(RemoteUtil.java:157)
at com.sun.proxy.$Proxy132.applyProfiles(Unknown Source)
at org.jetbrains.idea.maven.server.MavenServerManager.lambda$applyProfiles$3(MavenServerManager.java:531)
at org.jetbrains.idea.maven.server.RemoteObjectWrapper.perform(RemoteObjectWrapper.java:76)
... 35 more
Caused by: java.net.SocketException: Connection reset
at java.net.SocketInputStream.read(SocketInputStream.java:210)
at java.net.SocketInputStream.read(SocketInputStream.java:141)
at java.io.BufferedInputStream.fill(BufferedInputStream.java:246)
at java.io.BufferedInputStream.read(BufferedInputStream.java:265)
at java.io.DataInputStream.readByte(DataInputStream.java:265)
at sun.rmi.transport.StreamRemoteCall.executeCall(StreamRemoteCall.java:215)
... 51 more
2021-01-22 16:11:04,491 [1584309] ERROR - #org.jetbrains.idea.maven - IntelliJ IDEA 2018.3.2 Build #IU-183.4886.37
2021-01-22 16:11:04,491 [1584309] ERROR - #org.jetbrains.idea.maven - JDK: 1.8.0_152-release; VM: OpenJDK 64-Bit Server VM; Vendor: JetBrains s.r.o
2021-01-22 16:11:04,491 [1584309] ERROR - #org.jetbrains.idea.maven - OS: Windows 10
2021-01-22 16:11:04,507 [1584325] ERROR - #org.jetbrains.idea.maven - Last Action: Maven.ShowSettings