tomcat的版本为Tomcat8.5.24 log4j:ERROR Could not instantiate class . java.lang.ClassNotFoundException: DOMConfigurator at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1291) at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1119) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:264) at com.fr.third.apache.log4j.helpers.Loader.loadClass(Unknown Source) at com.fr.third.apache.log4j.helpers.OptionConverter.instantiateByClassName(Unknown Source) at com.fr.third.apache.log4j.helpers.OptionConverter.selectAndConfigure(Unknown Source) at com.fr.third.apache.log4j.LogManager.(Unknown Source) at com.fr.third.apache.log4j.PropertyConfigurator.configure(Unknown Source) at com.fr.general.FRLogger.(Unknown Source) at com.fr.general.FRLogger.getLogger(Unknown Source) at com.fr.general.FRLogger.(Unknown Source) at com.fr.register.Register.(Unknown Source) at com.fr.web.BaseServlet.init(Unknown Source) at com.fr.web.ReportServlet.init(Unknown Source) at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1183) at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1099) at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:989) at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4931) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5241) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:752) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:728) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:734) at org.apache.catalina.startup.HostConfig.manageApp(HostConfig.java:1736) 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.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:300) at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819) at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801) at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:482) at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:431) 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.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:300) at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819) at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801) at javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1468) at javax.management.remote.rmi.RMIConnectionImpl.access$300(RMIConnectionImpl.java:76) at javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:1309) at javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:1401) at javax.management.remote.rmi.RMIConnectionImpl.invoke(RMIConnectionImpl.java:829) 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 sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:357) at sun.rmi.transport.Transport$1.run(Transport.java:200) at sun.rmi.transport.Transport$1.run(Transport.java:197) at java.security.AccessController.doPrivileged(Native Method) at sun.rmi.transport.Transport.serviceCall(Transport.java:196) at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:568) at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:826) at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$0(TCPTransport.java:683) at java.security.AccessController.doPrivileged(Native Method) at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:682) 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) log4j:ERROR Could not instantiate configurator .