I'am using Zookeeper client API in java web application.When I shut down tomcat,I am getting this error :
2013-06-07 12:01:29,676 ERROR [org.apache.zookeeper.ClientCnxn] (xxx-startStop-1-SendThread(xxx.net:12183)) from xxx-startStop-1-SendThread(xxx.net:12183) java.lang.NoClassDefFoundError: org/apache/zookeeper/server/ZooTrace at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1115) Caused by: java.lang.ClassNotFoundException: org.apache.zookeeper.server.ZooTrace at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1711) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1556) ... 1 more at the same time,the following is also in catalina.out: INFO: Illegal access: this web application instance has been stopped already. Could not load org.apache.zookeeper.server.ZooTrace. The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. java.lang.IllegalStateException at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1597) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1556) at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1115) I searched google and mail list ,couldn't find any solution,please help me. Enviroment info: JDK:1.6.0_45 Tomcat:7.0.40 Zookeeper:3.4.5 Thanks, Bob