这么一个问题：结果是我的localhost单词写错了，白白浪费了十几分钟！
D:\softInstall\java\jdk-8u271\bin\java.exe -Dmaven.multiModuleProjectDirectory=F:\studyNote\maven\webapp\20201204\empsys -Dmaven.home=D:\softInstall\apache-maven-3.3.9 -Dclassworlds.conf=D:\softInstall\apache-maven-3.3.9\bin\m2.conf "-javaagent:D:\softInstall\IntelliJ IDEA 2018.1.6\lib\idea_rt.jar=53986:D:\softInstall\IntelliJ IDEA 2018.1.6\bin" -Dfile.encoding=UTF-8 -classpath D:\softInstall\apache-maven-3.3.9\boot\plexus-classworlds-2.5.2.jar org.codehaus.classworlds.Launcher -Didea.version=2018.1.6 -s D:\softInstall\apache-maven-3.3.9\conf\settings.xml -Dmaven.repo.local=F:\MavenRepository org.mybatis.generator:mybatis-generator-maven-plugin:1.3.7:generate -f pom.xml
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building empsys1 Maven Webapp 1.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- mybatis-generator-maven-plugin:1.3.7:generate (default-cli) @ empsys1 ---
[INFO] Connecting to the Database
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2.756 s
[INFO] Finished at: 2020-12-04T19:48:45+08:00
[INFO] Final Memory: 10M/489M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.7:generate (default-cli) on project empsys1: Communications link failure
[ERROR]
[ERROR] The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
[ERROR] -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException
Process finished with exit code 1