Tomcat_错误_InstanceAlreadyExistsException

错误原因:

//Host标签配置了appBase路径,会加载一次webapps内所有的项目
//下方又配置了项目路径
//导致springboot项目被重复加载.
<Host name="localhost" autoDeploy="true" unpackWARs="true" appBase="webapps">
//配置了项目路径,会让项目加载一次
<Context crossContext="true" reloadable="false" docBase="D:\apache-tomcat-portal\webapps\km_portal_server" path="/portal"/>

解决办法:

//将AppBase设置为空就可以了

<Host name="localhost" autoDeploy="true" unpackWARs="true" appBase="">

<Context crossContext="true" reloadable="false" docBase="D:\apache-tomcat-portal\webapps\km_portal_server" path="/portal"/>

报错信息:

03-Apr-2020 16:39:46.733 SEVERE [localhost-startStop-1] org.apache.catalina.core.ContainerBase.addChildInternal ContainerBase.addChild: start: 
 org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/km_portal_server]]
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
	at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
	at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
	at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
	at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:945)
	at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1795)
	at java.util.concurrent.Executors$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$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)
Caused by: org.springframework.jmx.export.UnableToRegisterMBeanException: Unable to register MBean [HikariDataSource (HikariCP)] with key 'dataSource'; nested exception is javax.management.InstanceAlreadyExistsException: com.zaxxer.hikari:name=dataSource,type=HikariDataSource
	at org.springframework.jmx.export.MBeanExporter.registerBeanNameOrInstance(MBeanExporter.java:625)
	at org.springframework.jmx.export.MBeanExporter.lambda$registerBeans$2(MBeanExporter.java:551)
	at java.util.HashMap.forEach(HashMap.java:1289)
	at org.springframework.jmx.export.MBeanExporter.registerBeans(MBeanExporter.java:551)
	at org.springframework.jmx.export.MBeanExporter.afterSingletonsInstantiated(MBeanExporter.java:434)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:866)
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:877)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549)
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:142)
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:775)
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:316)
	at org.springframework.boot.web.servlet.support.SpringBootServletInitializer.run(SpringBootServletInitializer.java:157)
	at org.springframework.boot.web.servlet.support.SpringBootServletInitializer.createRootApplicationContext(SpringBootServletInitializer.java:137)
	at org.springframework.boot.web.servlet.support.SpringBootServletInitializer.onStartup(SpringBootServletInitializer.java:91)
	at org.springframework.web.SpringServletContainerInitializer.onStartup(SpringServletContainerInitializer.java:171)
	at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5244)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	... 10 more
Caused by: javax.management.InstanceAlreadyExistsException: com.zaxxer.hikari:name=dataSource,type=HikariDataSource
	at com.sun.jmx.mbeanserver.Repository.addMBean(Repository.java:437)
	at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.registerWithRepository(DefaultMBeanServerInterceptor.java:1898)
	at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.registerDynamicMBean(DefaultMBeanServerInterceptor.java:966)
	at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.registerObject(DefaultMBeanServerInterceptor.java:900)
	at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.registerMBean(DefaultMBeanServerInterceptor.java:324)
	at com.sun.jmx.mbeanserver.JmxMBeanServer.registerMBean(JmxMBeanServer.java:522)
	at org.springframework.jmx.support.MBeanRegistrationSupport.doRegister(MBeanRegistrationSupport.java:137)
	at org.springframework.jmx.export.MBeanExporter.registerBeanInstance(MBeanExporter.java:671)
	at org.springframework.jmx.export.MBeanExporter.registerBeanNameOrInstance(MBeanExporter.java:615)
	... 27 more

03-Apr-2020 16:39:46.736 SEVERE [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployWAR Error deploying web application archive D:\apache-tomcat-portal\webapps\km_portal_server.war
 java.lang.IllegalStateException: ContainerBase.addChild: start: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/km_portal_server]]
	at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:729)
	at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
	at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
	at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:945)
	at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1795)
	at java.util.concurrent.Executors$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)