tomcat报错如下：
HTTP Status 404 - Servlet xxx is not available
type Status report
message Servlet xxx is not available
description The requested resource is not available.
Apache Tomcat/6.0.37
org.apache.catalina.core.StandardWrapperValve invoke
INFO: Servlet xxx is currently unavailable
解决方案： 查看是否正确生成class文件 1.clean project 2.清空tomcat缓存 3.重新发布工程