Struts2 unhandled exception

Struts has detected an unhandled exception:

Messages:	courseInfo Caught an exception while getting the property values of com.csljc.doraemon.trainingMgt.action.FeedBackAction@27de24 Caught an exception while getting the property values of com.csljc.doraemon.trainingMgt.action.FeedBackAction@27de24 - Class: ognl.OgnlRuntime File: OgnlRuntime.java Method: getMethodValue Line: 935 - ognl/OgnlRuntime.java:935:-1
File:	ognl/OgnlRuntime.java
Line number:	935

严重: Servlet.service() for servlet jsp threw exception

ognl.OgnlException: courseInfo [java.lang.NumberFormatException: null]

今天上午把一个struts内的方法名改为：get...()；出现上述错误。

总结 struts中除了属性的get set 方法 别的方法尽量别用get开头