java-spring boot在idea上面创建和导入别人的demo，运行主函数报这个错—

idea spring boot启动失败

每次启动spring boot都自动停止了，提示Disconnected from the target VM, address: '127.0.0.1:XXXXX', transport: 'socket'，每次端口都不一样，重启idea杀掉后台进程都不行，不知道为什么，新建一个空项目也是这样的问题，但是跑以前建的demo就没这个问题，求大神指导！！！

idea配置spring-boot，引入的test路径找不到

idea配置spring-boot，引入的test路径找不到 pom配置文件： ``` <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.1.3.RELEASE</version> <relativePath/>  </parent> <groupId>com.example</groupId> <artifactId>spring-boot</artifactId> <version>0.0.1-SNAPSHOT</version> <name>spring-boot</name> <description>Demo project for Spring Boot</description> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> </properties> <dependencies>  <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency>  <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency>  <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-configuration-processor</artifactId> <optional>true</optional> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> ``` 报错截图： ![图片说明](https://img-ask.csdn.net/upload/201903/12/1552370851_670003.png) 依赖包： ![图片说明](https://img-ask.csdn.net/upload/201903/12/1552370943_799650.png) ![图片说明](https://img-ask.csdn.net/upload/201903/12/1552370954_624153.png)

我需要一个整合spring boot shiro JWT 的多realm登录认证的demo

<dependency> <groupId>org.apache.shiro</groupId> <artifactId>shiro-spring</artifactId> <version>1.4.0</version> </dependency> <dependency> <groupId>org.apache.shiro</groupId> <artifactId>shiro-ehcache</artifactId> <version>1.4.0</version> </dependency>  <dependency> <groupId>com.auth0</groupId> <artifactId>java-jwt</artifactId> <version>3.4.1</version> </dependency> 依赖整合jwt和shiro安全框架,实现token认证我需要demo文件

spring+ boot+ shiro+ jwt怎么监听用户是否在线

请详细说明,不要引用网上的各种帖子,我都试过了,有各种各样的漏洞,最好能发过来个demo

Springboot2.2.2不能连接数据库

1.写一个体验redis缓存的demo，不能连接数据库。导入其他人的项目可以，连接自己的数据库，可以连接成功。确定数据库连接信息没有写错。参考网上,修改mysql-connector-java的版本也没有用。系统环境：java-1.8; mysql-5.1.62; IDEA 2019-1.4;SpringBoot 2.2.2; 2.pom文件： <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.2.2.RELEASE</version> <relativePath/>  </parent> <groupId>com.example</groupId> <artifactId>cache</artifactId> <version>0.0.1-SNAPSHOT</version> <name>cache</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-cache</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>2.1.1</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.34</version> <scope>runtime</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> <exclusions> <exclusion> <groupId>org.junit.vintage</groupId> <artifactId>junit-vintage-engine</artifactId> </exclusion> </exclusions> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> 3.配置文件 ![图片说明](https://img-ask.csdn.net/upload/202001/06/1578275877_830078.png) 4.报错信息 ![图片说明](https://img-ask.csdn.net/upload/202001/06/1578276565_257380.png) ![图片说明](https://img-ask.csdn.net/upload/202001/06/1578275918_258494.png) ![图片说明](https://img-ask.csdn.net/upload/202001/06/1578275931_720085.png) ![图片说明](https://img-ask.csdn.net/upload/202001/06/1578275953_50439.png) ![图片说明](https://img-ask.csdn.net/upload/202001/06/1578275966_288013.png)

idea配置mybits generate时报错，请问是哪配错了吗？

报错说找不到driver-class-name核对了很多次都没问题啊报错： ``` D:\jdk1.8.0_121\bin\java.exe -Dmaven.multiModuleProjectDirectory=D:\mycode\demo_mybits\demo "-Dmaven.home=D:\software\idea\IntelliJ IDEA 2018.2.6\plugins\maven\lib\maven3" "-Dclassworlds.conf=D:\software\idea\IntelliJ IDEA 2018.2.6\plugins\maven\lib\maven3\bin\m2.conf" "-javaagent:D:\software\idea\IntelliJ IDEA 2018.2.6\lib\idea_rt.jar=7115:D:\software\idea\IntelliJ IDEA 2018.2.6\bin" -Dfile.encoding=UTF-8 -classpath "D:\software\idea\IntelliJ IDEA 2018.2.6\plugins\maven\lib\maven3\boot\plexus-classworlds-2.5.2.jar" org.codehaus.classworlds.Launcher -Didea.version=2018.2.6 mybatis-generator:generate -e [INFO] Error stacktraces are turned on. [INFO] Scanning for projects... [INFO] [INFO] ------------------------------------------------------------------------ [INFO] Building demo 0.0.1-SNAPSHOT [INFO] ------------------------------------------------------------------------ [INFO] [INFO] --- mybatis-generator-maven-plugin:1.3.2:generate (default-cli) @ demo --- [INFO] Connecting to the Database [INFO] ------------------------------------------------------------------------ [INFO] BUILD FAILURE [INFO] ------------------------------------------------------------------------ [INFO] Total time: 1.637 s [INFO] Finished at: 2019-11-11T09:52:35+08:00 [INFO] Final Memory: 14M/245M [INFO] ------------------------------------------------------------------------ [ERROR] Failed to execute goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate (default-cli) on project demo: Execution default-cli of goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate failed: Exception getting JDBC Driver: {spring.datasource.driver-class-name} -> [Help 1] org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate (default-cli) on project demo: Execution default-cli of goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate failed: Exception getting JDBC Driver at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:212) at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153) at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145) at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:116) at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:80) at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51) at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128) at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:307) at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:193) at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:106) at org.apache.maven.cli.MavenCli.execute(MavenCli.java:863) at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:288) at org.apache.maven.cli.MavenCli.main(MavenCli.java:199) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289) at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229) at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415) at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356) at org.codehaus.classworlds.Launcher.main(Launcher.java:47) Caused by: org.apache.maven.plugin.PluginExecutionException: Execution default-cli of goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate failed: Exception getting JDBC Driver at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:145) at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:207) ... 21 more Caused by: java.lang.RuntimeException: Exception getting JDBC Driver at org.mybatis.generator.internal.db.ConnectionFactory.getDriver(ConnectionFactory.java:85) at org.mybatis.generator.internal.db.ConnectionFactory.getConnection(ConnectionFactory.java:54) at org.mybatis.generator.config.Context.getConnection(Context.java:526) at org.mybatis.generator.config.Context.introspectTables(Context.java:436) at org.mybatis.generator.api.MyBatisGenerator.generate(MyBatisGenerator.java:222) at org.mybatis.generator.maven.MyBatisGeneratorMojo.execute(MyBatisGeneratorMojo.java:203) at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134) ... 22 more Caused by: java.lang.ClassNotFoundException: {spring.datasource.driver-class-name} at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:50) at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadClass(ClassRealm.java:271) at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:247) at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:239) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:348) at org.mybatis.generator.internal.ObjectFactory.internalClassForName(ObjectFactory.java:150) at org.mybatis.generator.internal.ObjectFactory.externalClassForName(ObjectFactory.java:121) at org.mybatis.generator.internal.db.ConnectionFactory.getDriver(ConnectionFactory.java:82) ... 28 more [ERROR] [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/PluginExecutionException Process finished with exit code 1 ``` application.properties ``` ## 服务器端口，如果不配置默认是8080端口 server.port=9090 ## 数据库设置 spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver spring.datasource.url=jdbc:mysql://localhost:3306/boot_demo?serverTimezone=UTC&useUnicode=true&characterEncoding=utf8 spring.datasource.username=root spring.datasource.password=x5 ## mybatis配置 # 参数类型的包别名设置 mybatis.typeAliasesPackage=com.example.demo.model # 指向映射xml文件目录 mybatis.mapperLocations=classpath:mapper/*.xml pagehelper.helperDialect=mysql pagehelper.reasonable=true pagehelper.supportMethodsArguments=true pagehelper.params=count=countSql ``` pom.xml ``` <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.2.0.RELEASE</version> <relativePath/>  </parent> <groupId>com.example</groupId> <artifactId>demo</artifactId> <version>0.0.1-SNAPSHOT</version> <name>demo</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.3.2</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>com.github.pagehelper</groupId> <artifactId>pagehelper-spring-boot-starter</artifactId> <version>1.2.10</version> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> <plugin> <groupId>org.mybatis.generator</groupId> <artifactId>mybatis-generator-maven-plugin</artifactId> <version>1.3.7</version> <configuration> <verbose>true</verbose> <overwrite>true</overwrite> </configuration> <dependencies> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>8.0.18</version> <scope>runtime</scope> </dependency> </dependencies> </plugin> </plugins> </build> </project> ``` generatorConfig.xml ``` <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE generatorConfiguration PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN" "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd"> <generatorConfiguration>  <properties resource="application.properties"></properties>  <context id="default">  <commentGenerator>  <property name="suppressDate" value="true" />  <property name="suppressAllComments" value="true" /> </commentGenerator>  <jdbcConnection driverClass="{spring.datasource.driver-class-name}" connectionURL="{spring.datasource.url}" userId="{spring.datasource.username}" password="{spring.datasource.password}"> <property name="nullCatalogMeansCurrent" value="true" /> </jdbcConnection>  <javaTypeResolver>  <property name="forceBigDecimals" value="false" /> </javaTypeResolver>   <javaModelGenerator targetPackage="com.example.demo.model" targetProject="src/main/java">  <property name="enableSubPackages" value="false" />  <property name="constructorBased" value="true" />  <property name="trimStrings" value="true" />  <property name="immutable" value="false" /> </javaModelGenerator>  <sqlMapGenerator targetPackage="mapper" targetProject="src/main/resources">  <property name="enableSubPackages" value="false" />  <property name="trimStrings" value="true"/> </sqlMapGenerator>  <javaClientGenerator type="XMLMAPPER" targetPackage="com.example.demo.repository" targetProject="src/main/java">  <property name="enableSubPackages" value="false" /> </javaClientGenerator>    <table tableName="user" domainObjectName="User" enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false" enableSelectByExample="false" selectByExampleQueryId="false"> </table> </context> </generatorConfiguration> ```

springboot2.1 引入spring-boot-starter-web时启动报错

``` java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [NonLoginAuthenticator[StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]] at java.util.concurrent.FutureTask.report(FutureTask.java:122) [na:1.8.0_191] at java.util.concurrent.FutureTask.get(FutureTask.java:192) [na:1.8.0_191] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:914) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:831) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1382) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1372) [tomcat-embed-core-9.0.14.jar:9.0.14] at java.util.concurrent.FutureTask.run$$$capture(FutureTask.java:266) [na:1.8.0_191] at java.util.concurrent.FutureTask.run(FutureTask.java) [na:1.8.0_191] at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) [tomcat-embed-core-9.0.14.jar:9.0.14] at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:134) [na:1.8.0_191] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:907) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:262) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.StandardService.startInternal(StandardService.java:423) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:933) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.startup.Tomcat.start(Tomcat.java:398) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:106) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.<init>(TomcatWebServer.java:86) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getTomcatWebServer(TomcatServletWebServerFactory.java:415) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getWebServer(TomcatServletWebServerFactory.java:174) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:181) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:154) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:540) [spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:142) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:775) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:316) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at com.example.demo.DemoApplication.main(DemoApplication.java:10) [classes/:na] Caused by: org.apache.catalina.LifecycleException: Failed to start component [NonLoginAuthenticator[StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]] at org.apache.catalina.util.LifecycleBase.handleSubClassException(LifecycleBase.java:441) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:198) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.StandardPipeline.startInternal(StandardPipeline.java:181) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5041) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1382) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1372) [tomcat-embed-core-9.0.14.jar:9.0.14] at java.util.concurrent.FutureTask.run$$$capture(FutureTask.java:266) [na:1.8.0_191] at java.util.concurrent.FutureTask.run(FutureTask.java) [na:1.8.0_191] at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) [tomcat-embed-core-9.0.14.jar:9.0.14] at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:134) [na:1.8.0_191] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:907) [tomcat-embed-core-9.0.14.jar:9.0.14] ... 30 common frames omitted Caused by: java.lang.NoSuchMethodError: javax.servlet.ServletContext.getVirtualServerName()Ljava/lang/String; at org.apache.catalina.authenticator.AuthenticatorBase.startInternal(AuthenticatorBase.java:1178) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.14.jar:9.0.14] ... 41 common frames omitted 2019-01-21 22:19:30.303 ERROR 30556 --- [ main] org.apache.catalina.core.ContainerBase : A child container failed during start java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: A child container failed during start at java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[na:1.8.0_191] at java.util.concurrent.FutureTask.get(FutureTask.java:192) ~[na:1.8.0_191] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:914) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:262) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.StandardService.startInternal(StandardService.java:423) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:933) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.startup.Tomcat.start(Tomcat.java:398) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:106) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.<init>(TomcatWebServer.java:86) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getTomcatWebServer(TomcatServletWebServerFactory.java:415) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getWebServer(TomcatServletWebServerFactory.java:174) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:181) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:154) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:540) [spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:142) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:775) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:316) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at com.example.demo.DemoApplication.main(DemoApplication.java:10) [classes/:na] Caused by: org.apache.catalina.LifecycleException: A child container failed during start at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:926) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:831) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1382) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1372) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at java.util.concurrent.FutureTask.run$$$capture(FutureTask.java:266) ~[na:1.8.0_191] at java.util.concurrent.FutureTask.run(FutureTask.java) ~[na:1.8.0_191] at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:134) ~[na:1.8.0_191] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:907) ~[tomcat-embed-core-9.0.14.jar:9.0.14] ... 21 common frames omitted Caused by: java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [NonLoginAuthenticator[StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]] at java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[na:1.8.0_191] at java.util.concurrent.FutureTask.get(FutureTask.java:192) ~[na:1.8.0_191] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:914) ~[tomcat-embed-core-9.0.14.jar:9.0.14] ... 30 common frames omitted Caused by: org.apache.catalina.LifecycleException: Failed to start component [NonLoginAuthenticator[StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]] at org.apache.catalina.util.LifecycleBase.handleSubClassException(LifecycleBase.java:441) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:198) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.StandardPipeline.startInternal(StandardPipeline.java:181) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5041) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1382) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1372) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at java.util.concurrent.FutureTask.run$$$capture(FutureTask.java:266) ~[na:1.8.0_191] at java.util.concurrent.FutureTask.run(FutureTask.java) ~[na:1.8.0_191] at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:134) ~[na:1.8.0_191] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:907) ~[tomcat-embed-core-9.0.14.jar:9.0.14] ... 30 common frames omitted Caused by: java.lang.NoSuchMethodError: javax.servlet.ServletContext.getVirtualServerName()Ljava/lang/String; at org.apache.catalina.authenticator.AuthenticatorBase.startInternal(AuthenticatorBase.java:1178) ~[tomcat-embed-core-9.0.14.jar:9.0.14] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) [tomcat-embed-core-9.0.14.jar:9.0.14] ... 41 common frames omitted Disconnected from the target VM, address: '127.0.0.1:57321', transport: 'socket' 2019-01-21 22:19:30.321 INFO 30556 --- [ main] o.apache.catalina.core.StandardService : Stopping service [Tomcat] 2019-01-21 22:19:30.322 WARN 30556 --- [ main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat 2019-01-21 22:19:30.322 INFO 30556 --- [ main] ConditionEvaluationReportLoggingListener : Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled. 2019-01-21 22:19:30.333 ERROR 30556 --- [ main] o.s.b.d.LoggingFailureAnalysisReporter : *************************** APPLICATION FAILED TO START *************************** Description: An attempt was made to call the method javax.servlet.ServletContext.getVirtualServerName()Ljava/lang/String; but it does not exist. Its class, javax.servlet.ServletContext, is available from the following locations: jar:file:/C:/Program%20Files%20(x86)/JAVA/JDK/jre/lib/ext/servlet-api.jar!/javax/servlet/ServletContext.class jar:file:/C:/Mavn/maven-repository/org/apache/tomcat/embed/tomcat-embed-core/9.0.14/tomcat-embed-core-9.0.14.jar!/javax/servlet/ServletContext.class It was loaded from the following location: file:/C:/Program%20Files%20(x86)/JAVA/JDK/jre/lib/ext/servlet-api.jar Action: Correct the classpath of your application so that it contains a single, compatible version of javax.servlet.ServletContext Process finished with exit code 1 ``` idea生成的springboot项目，当pom文件引入spring-boot-starter-web时启动报错

model内设置的值在html界面显示乱码，为何修改idea内的编码后解决了此问题？

html代码 ``` <html xmlns:th="http://www.thymeleaf.org"> <head> <title>错误界面</title> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/> <link rel="stylesheet" href="/css/bootstrap.min.css"> <link rel="stylesheet" href="/css/bootstrap-theme.min.css"> <link rel="stylesheet" href="/css/demo.css"> <script src="/js/jquery-3.4.1.min.js"></script> <script src="/js/bootstrap.min.js"></script> </head> <body> <p th:if="${message==null}">页面迷路了，要不待会再来？</p> <p th:if="${message!=null}"><span th:text="${message}"></span></p> </body> ``` <br> <br> <br> <br> Controller代码 ``` package com.example.demo.advice; import org.springframework.http.HttpStatus; import org.springframework.ui.Model; import org.springframework.web.bind.annotation.ControllerAdvice; import org.springframework.web.bind.annotation.ExceptionHandler; import org.springframework.web.servlet.ModelAndView; import javax.servlet.http.HttpServletRequest; @ControllerAdvice public class CustomizeExceptionHandler { @ExceptionHandler(Exception.class) ModelAndView handle(HttpServletRequest request, Throwable ex , Model model) { HttpStatus status = getStatus(request); String error = "乱码"; model.addAttribute("message","乱码"); return new ModelAndView("error"); } private HttpStatus getStatus(HttpServletRequest request) { Integer statusCode = (Integer) request.getAttribute("javax.servlet.error.status_code"); if (statusCode == null) { return HttpStatus.INTERNAL_SERVER_ERROR; } return HttpStatus.valueOf(statusCode); } } ``` <br> <br> <br> <br> <br> <br> <br> 开发工具为IDEA，框架为spring boot，html界面已设为UTF-8 <br> <br> 下图为idea设置编码的位置<br> ![图片说明](https://img-ask.csdn.net/upload/201911/11/1573473948_53268.png) 当Controller的代码使用的编码是gb2312时，html界面通过“${message}”取到的值是正常的。<br> 将代码的编码设为与html界面相同的utf-8时，“${message}”取到的值却是乱码的。<br> 为何使用相同的编码会导致乱码，而使用不同的编码却能解决问题？

java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]

idea中springboot内置tomcat起不起来 pom.xml： <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.2.1.RELEASE</version> <relativePath/>  </parent> <groupId>com.aipuer</groupId> <artifactId>spring-boot</artifactId> <version>0.0.1-SNAPSHOT</version> <name>spring-boot</name> <description>Demo project for Spring Boot</description> <properties> <java.version>11</java.version> </properties> <dependencies>  <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency>  <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-thymeleaf</artifactId> </dependency>  <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.1.1</version> </dependency>  <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency>  <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.0.9</version> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <version>1.5.9.RELEASE</version> </plugin> </plugins> </build> </project> 错误代码： 2019-12-03 10:08:21.181 INFO 7936 --- [ main] com.aipuer.springboot.Application : Starting Application on PC-20191121IKBV with PID 7936 (E:\java\develop\javacode\spring-boot\target\classes started by Administrator in E:\java\develop\javacode\spring-boot) 2019-12-03 10:08:21.183 INFO 7936 --- [ main] com.aipuer.springboot.Application : No active profile set, falling back to default profiles: default 2019-12-03 10:08:21.554 WARN 7936 --- [ main] o.m.s.mapper.ClassPathMapperScanner : No MyBatis mapper was found in '[com.aipuer.springboot]' package. Please check your configuration. 2019-12-03 10:08:21.839 INFO 7936 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8080 (http) 2019-12-03 10:08:21.844 INFO 7936 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat] 2019-12-03 10:08:21.844 INFO 7936 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.27] 2019-12-03 10:08:21.888 ERROR 7936 --- [ main] org.apache.catalina.core.ContainerBase : A child container failed during start java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [NonLoginAuthenticator[StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]] at java.base/java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[na:na] at java.base/java.util.concurrent.FutureTask.get(FutureTask.java:191) ~[na:na] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:916) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:841) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[na:na] at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140) ~[na:na] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:262) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardService.startInternal(StandardService.java:421) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:930) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.startup.Tomcat.start(Tomcat.java:459) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:107) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.<init>(TomcatWebServer.java:88) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getTomcatWebServer(TomcatServletWebServerFactory.java:438) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getWebServer(TomcatServletWebServerFactory.java:191) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:180) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:153) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:544) ~[spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at com.aipuer.springboot.Application.main(Application.java:10) ~[classes/:na] Caused by: org.apache.catalina.LifecycleException: Failed to start component [NonLoginAuthenticator[StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]] at org.apache.catalina.util.LifecycleBase.handleSubClassException(LifecycleBase.java:440) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:198) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardPipeline.startInternal(StandardPipeline.java:176) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5063) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[na:na] at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140) ~[na:na] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909) ~[tomcat-embed-core-9.0.27.jar:9.0.27] ... 29 common frames omitted Caused by: java.lang.NoSuchMethodError: 'java.lang.String javax.servlet.ServletContext.getVirtualServerName()' at org.apache.catalina.authenticator.AuthenticatorBase.startInternal(AuthenticatorBase.java:1220) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] ... 39 common frames omitted 2019-12-03 10:08:21.889 ERROR 7936 --- [ main] org.apache.catalina.core.ContainerBase : A child container failed during start java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: A child container failed during start at java.base/java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[na:na] at java.base/java.util.concurrent.FutureTask.get(FutureTask.java:191) ~[na:na] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:916) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:262) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardService.startInternal(StandardService.java:421) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:930) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.startup.Tomcat.start(Tomcat.java:459) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:107) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.<init>(TomcatWebServer.java:88) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getTomcatWebServer(TomcatServletWebServerFactory.java:438) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getWebServer(TomcatServletWebServerFactory.java:191) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:180) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:153) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:544) ~[spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at com.aipuer.springboot.Application.main(Application.java:10) ~[classes/:na] Caused by: org.apache.catalina.LifecycleException: A child container failed during start at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:928) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:841) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[na:na] at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140) ~[na:na] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909) ~[tomcat-embed-core-9.0.27.jar:9.0.27] ... 21 common frames omitted Caused by: java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [NonLoginAuthenticator[StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]] at java.base/java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[na:na] at java.base/java.util.concurrent.FutureTask.get(FutureTask.java:191) ~[na:na] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:916) ~[tomcat-embed-core-9.0.27.jar:9.0.27] ... 29 common frames omitted Caused by: org.apache.catalina.LifecycleException: Failed to start component [NonLoginAuthenticator[StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]] at org.apache.catalina.util.LifecycleBase.handleSubClassException(LifecycleBase.java:440) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:198) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardPipeline.startInternal(StandardPipeline.java:176) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5063) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[na:na] at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140) ~[na:na] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909) ~[tomcat-embed-core-9.0.27.jar:9.0.27] ... 29 common frames omitted Caused by: java.lang.NoSuchMethodError: 'java.lang.String javax.servlet.ServletContext.getVirtualServerName()' at org.apache.catalina.authenticator.AuthenticatorBase.startInternal(AuthenticatorBase.java:1220) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] ... 39 common frames omitted 2019-12-03 10:08:21.889 INFO 7936 --- [ main] o.apache.catalina.core.StandardService : Stopping service [Tomcat] 2019-12-03 10:08:21.900 WARN 7936 --- [ main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat 2019-12-03 10:08:21.906 INFO 7936 --- [ main] ConditionEvaluationReportLoggingListener : Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled. 2019-12-03 10:08:21.909 ERROR 7936 --- [ main] o.s.b.d.LoggingFailureAnalysisReporter : *************************** APPLICATION FAILED TO START *************************** Description: An attempt was made to call a method that does not exist. The attempt was made from the following location: org.apache.catalina.authenticator.AuthenticatorBase.startInternal(AuthenticatorBase.java:1220) The following method did not exist: 'java.lang.String javax.servlet.ServletContext.getVirtualServerName()' The method's class, javax.servlet.ServletContext, is available from the following locations: jar:file:/E:/java/develop/javacode/spring-boot/lib/javaee.jar!/javax/servlet/ServletContext.class jar:file:/E:/maven/maven_repository/org/apache/tomcat/embed/tomcat-embed-core/9.0.27/tomcat-embed-core-9.0.27.jar!/javax/servlet/ServletContext.class It was loaded from the following location: file:/E:/java/develop/javacode/spring-boot/lib/javaee.jar Action: Correct the classpath of your application so that it contains a single, compatible version of javax.servlet.ServletContext Disconnected from the target VM, address: '127.0.0.1:52758', transport: 'socket' Process finished with exit code 1

springboot2.2.0项目无法使用@EnableFeignClients已添加starter-openfeign和openfeign-core

环境： maven3.0+springboot2.2.0 想做微服务调用使用feign，启动类添加@EnableDiscoveryClient和@EnableDiscoveryClient pom文件添加： ``` <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.2.0.RELEASE</version> <relativePath/>  </parent> <groupId>com.example</groupId> <artifactId>consumer</artifactId> <version>0.0.1-SNAPSHOT</version> <name>consumer</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-eureka</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId> <version>2.1.1.RELEASE</version> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-feign</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-openfeign-core</artifactId> <version>2.0.0.RC1</version> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-openfeign</artifactId> <version>2.0.0.RC1</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> <exclusions> <exclusion> <groupId>org.junit.vintage</groupId> <artifactId>junit-vintage-engine</artifactId> </exclusion> </exclusions> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> ``` 如果不添加spring-cloud-openfeign-core，注解无法使用。如果添加了他，启动项目时报错context找不到。真心是无解了。。。。这springboot2.2.0怎么这么多坑

spring cloud feign注入失败，basePackages加了也没有起作用

![图片说明](https://img-ask.csdn.net/upload/201908/22/1566441715_328431.png) ```java package com.example.eurekaclient; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.client.circuitbreaker.EnableCircuitBreaker; import org.springframework.cloud.client.discovery.EnableDiscoveryClient; import org.springframework.cloud.netflix.eureka.EnableEurekaClient; import org.springframework.cloud.netflix.hystrix.EnableHystrix; import org.springframework.cloud.openfeign.EnableFeignClients; import org.springframework.context.annotation.ComponentScan; //import org.springframework.cloud.netflix.hystrix.dashboard.EnableHystrixDashboard; @SpringBootApplication @EnableDiscoveryClient @EnableEurekaClient @EnableFeignClients(basePackages ={"com.example.eurekaclient.common"}) @EnableHystrix //@EnableHystrixDashboard @EnableCircuitBreaker public class EurekaclientApplication { public static void main(String[] args) { SpringApplication.run(EurekaclientApplication.class, args); } } ``` ``` package com.example.eurekaclient.common; import org.springframework.cloud.openfeign.FeignClient; import org.springframework.stereotype.Component; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RequestParam; /** * @author ： yy * @date ：Created in 19-8-21 下午2:07 * @description： * @modified By： * @version: $ */ @FeignClient(name = "SHOP-SERVER") @Component public interface HelloRemote { @GetMapping(value = "/hello") String hello(@RequestParam(value = "name")String name); } ``` ```xml <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.1.6.RELEASE</version> <relativePath/>  </parent> <groupId>com.example</groupId> <artifactId>eurekaclient</artifactId> <version>0.0.1-SNAPSHOT</version> <name>eurekaclient</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> <spring-cloud.version>Greenwich.SR2</spring-cloud.version> </properties> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-config</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-bus-amqp</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-amqp</artifactId> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <version>1.18.8</version> </dependency>                            <dependency> <groupId>com.netflix.hystrix</groupId> <artifactId>hystrix-javanica</artifactId> <version>RELEASE</version> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-openfeign</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-netflix-hystrix-dashboard</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-archaius</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-hystrix</artifactId> <version>2.1.1.RELEASE</version> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-netflix-hystrix</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-openfeign-core</artifactId> <version>2.1.2.RELEASE</version> <scope>compile</scope> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>${spring-cloud.version}</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> ```

为什么我spring mvc视图解析器一直404?

这是我的Application ``` package cn.edu.bzu.chapter9; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication(scanBasePackages = "cn.edu.bzu.chapter9") public class Chapter9Application { public static void main(String[] args) { SpringApplication.run(Chapter9Application.class, args); } } ``` 这是我的controller ``` package cn.edu.bzu.chapter9.controller; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; @Controller public class FoodController { @RequestMapping("/index") public String index(){ return "index"; } } ``` 这是我的配置文件 ``` spring.mvc.view.prefix=/WEB-INF/jsp/ spring.mvc.view.suffix=.jsp ``` 这是我的项目结构 ![图片说明](https://img-ask.csdn.net/upload/201906/27/1561633944_771999.png) 这是我的pop.xml ``` <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.1.6.RELEASE</version> <relativePath/>  </parent> <groupId>cn.edu.bzu</groupId> <artifactId>chapter9</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>war</packaging> <name>chapter9</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-tomcat</artifactId> <scope>provided</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjrt</artifactId> <version>${aspectj.version}</version> </dependency> <dependency> <groupId>org.apache.tomcat.embed</groupId> <artifactId>tomcat-embed-jasper</artifactId> <scope>provided</scope> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>jstl</artifactId> <version>1.2</version> <scope>provided</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> ```

小白提问idea怎么创建maven 按照教程一直报错啊

http://www.cnblogs.com/-xuzhankun/p/6627424.html教程 ![点击完这些后 idea 就报错了 dom4j的问题么](http://images2015.cnblogs.com/blog/959364/201703/959364-20170331121900180-1689499358.png) "C:\Program Files\Java\jdk1.8.0_60\bin\java" -Dmaven.multiModuleProjectDirectory=C:\Users\Administrator\AppData\Local\Temp\archetypetmp -Dmaven.multiModuleProjectDirectory=$M2_HOME -Dmaven.home=E:\maven\apache-maven-3.3.9 -Dclassworlds.conf=E:\maven\apache-maven-3.3.9\bin\m2.conf -Dfile.encoding=UTF-8 -classpath E:\maven\apache-maven-3.3.9\boot\plexus-classworlds-2.5.2.jar org.codehaus.classworlds.Launcher -Didea.version=2017.2.2 -s E:\maven\apache-maven-3.3.9\conf\settings.xml -DskipTests=true -DinteractiveMode=false -DgroupId=cn.deyou.demo1 -DartifactId=spring_b_m -Dversion=1.0-SNAPSHOT -DarchetypeGroupId=org.apache.maven.archetypes -DarchetypeArtifactId=maven-archetype-webapp -DarchetypeVersion=RELEASE org.apache.maven.plugins:maven-archetype-plugin:RELEASE:generate [INFO] Scanning for projects... [INFO] [INFO] ------------------------------------------------------------------------ [INFO] Building Maven Stub Project (No POM) 1 [INFO] ------------------------------------------------------------------------ [INFO] [INFO] >>> maven-archetype-plugin:3.0.1:generate (default-cli) > generate-sources @ standalone-pom >>> [INFO] [INFO] <<< maven-archetype-plugin:3.0.1:generate (default-cli) < generate-sources @ standalone-pom <<< [INFO] [INFO] --- maven-archetype-plugin:3.0.1:generate (default-cli) @ standalone-pom --- [WARNING] Error injecting: org.apache.maven.archetype.common.DefaultPomManager java.lang.NoClassDefFoundError: org/dom4j/DocumentException at java.lang.Class.getDeclaredMethods0(Native Method) ........ at org.codehaus.classworlds.Launcher.main(Launcher.java:47) [WARNING] Error injecting: org.apache.maven.archetype.creator.FilesetArchetypeCreator java.lang.NoClassDefFoundError: org/dom4j/DocumentException at java.lang.Class.getDeclaredMethods0(Native Method) ........ at org.codehaus.classworlds.Launcher.main(Launcher.java:47) [WARNING] Error injecting: org.apache.maven.archetype.DefaultArchetypeManager java.lang.NoClassDefFoundError: org/dom4j/DocumentException .............................

spring cloud 报无法使用内置服务器

![图片说明](https://img-ask.csdn.net/upload/201902/22/1550788109_933604.png) 明明在本地注册运行没有任何问题到了服务器上一直报这个错误 ```<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.19.RELEASE</version> <relativePath/>  </parent> <groupId>com.cglm</groupId> <artifactId>eureka</artifactId> <version>0.0.1-SNAPSHOT</version> <name>eureka</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> <spring-cloud.version>Edgware.SR5</spring-cloud.version> </properties> <dependencies> <dependency> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> <version>3.1.0</version> <scope>provided</scope> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-config</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>${spring-cloud.version}</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> ```

Springboot启动报错一个是找不到url 一个是找不到dao

## 之前一直启动都没有问题，今天突然发现启动不了 ![图片说明](https://img-ask.csdn.net/upload/201910/10/1570671612_490949.jpg) ## 然后我把启动的位置改成@SpringBootApplication(exclude = DataSourceAutoConfiguration.class) ``` package com.mall.shopping.demo; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration; /*@SpringBootApplication*/ @SpringBootApplication(exclude = DataSourceAutoConfiguration.class) public class DemoApplication { public static void main(String[] args) { SpringApplication.run(DemoApplication.class, args); } } ``` ## 然后会报新的错： ![图片说明](https://img-ask.csdn.net/upload/201910/10/1570671806_766601.jpg) # 到现在没找到新错误的原因还是在报找不到dao的错误。 ## 实体类代码： ![图片说明](https://img-ask.csdn.net/upload/201910/10/1570672651_585106.jpg) ## controller代码： ``` package com.mall.shopping.demo.controller; import com.mall.shopping.demo.services.UserService; import com.mall.shopping.demo.vo.Huser; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.servlet.ModelAndView; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.util.Iterator; import java.util.List; @Controller public class UserController { @Autowired private UserService userService; @RequestMapping("/tiao") public ModelAndView zhuan() { ModelAndView modelAndView = new ModelAndView("loginindex"); return modelAndView; } @RequestMapping("/tiao1") public ModelAndView zhuan1() { ModelAndView modelAndView = new ModelAndView("adminindex"); return modelAndView; } @RequestMapping("/Userlogin") public String userlogin(HttpServletRequest request, HttpServletResponse response) { String username = (String) request.getParameter("username"); String userpwd = (String)request.getParameter("userpwd"); List<Huser> huser = userService.userlogin(); Iterator iter = huser.iterator(); while(iter.hasNext()){ Huser ha = (Huser) iter.next(); if(username.equals(ha.getHuser())) { if(userpwd.equals(ha.getHpwd())) { return "redirect:/tiao1"; } else { return "redirect:/tiao"; } } } return "redirect:/tiao"; } } ``` ## services代码： ``` package com.mall.shopping.demo.services; import com.mall.shopping.demo.dao.UserDao; import com.mall.shopping.demo.vo.Huser; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import java.util.List; @Service public class UserService { @Autowired private UserDao userDao; public List<Huser> userlogin(){ return userDao.userlogin();} } ``` ## daoceng代码： ``` package com.mall.shopping.demo.dao; import com.mall.shopping.demo.vo.Huser; import org.apache.ibatis.annotations.Mapper; import org.springframework.stereotype.Repository; import java.util.List; @Repository @Mapper public interface UserDao { List<Huser>userlogin(); } ``` ## 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