The Struts dispatcher cannot be found. This is usually caused by using Struts

1.The Struts dispatcher cannot be found.  This is usually caused by using Struts tags without the associated filter. Strut   
2.s tags are only usable when the request has passed through its servlet filter, which initializes the Struts dispatcher n   
3.eeded for this tag. - [unknown location] 

解决： 
web.xml 中添加一个filter 
          <filter-mapping> 
<filter-name>struts2</filter-name> 
<url-pattern>*.jsp</url-pattern> 
</filter-mapping> 
<filter-mapping> 
<filter-name>struts2</filter-name> 
<url-pattern>/action/*</url-pattern> 
</filter-mapping>