我有：

17-Nov-2015 17:53:22.314 SEVERE [localhost-startStop-1] org.apache.catalina.core.StandardContext.filterStart Excepción arrancando filtro HTTPMonitorFilter
 java.lang.ClassNotFoundException: org.netbeans.modules.web.monitor.server
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1333)
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1167)
    at org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:520)
    at org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:501)
    at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:120)
    at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:258)
    at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:105)
    at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4583)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5207)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    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.deployDescriptor(HostConfig.java:586)
    at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1780)
    at java.util.concurrent.Executors$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)

理论上 org-netbeans-modules-web-httpmonitor.jar 包含类... MonitorFilter ，所以我把

org-netbeans-modules-web-httpmonitor.jar

在路径 /usr/lib/jvm/java-8-oracle/jre/lib/ext/ ...并检查运行过程：

lsof -p 28083 | grep jar | grep org-netbeans-modules-web-httpmonitor.jar

并且：

java 28083 darkglam mem REG 8,8 209867 525442 /usr/lib/jvm/java-8-oracle/jre/lib/ext/org-netbeans-modules-web-httpmonitor.jar

但例外还在这里......我做错了什么？

java tomcat netbeans