why error-page in web.xml cannot capture exceptions thrown from struts2 prepare method

i declare a global exception handler in web.xml

<error-page>
<exception-type>java.lang.Throwa开发者_如何学运维ble</exception-type>
<location>/exceptionHandler</location>
</error-page>

it works fine most of the time. But it cannot capture the exceptions thrown from the prepare method in struts2 actions

anyone know why

---

Probably because Struts2's ExceptionMappingInterceptor catches exceptions and maps them to error pages itself.

You can use the following in your struts.xml:

<global-results>
    <result name="error">/WEB-INF/error.jsp</result>
</global-results>

<global-exception-mappings>
    <exception-mapping exception="java.lang.Exception" result="error"/>
</global-exception-mappings>

Alternatively, you could remove the ExceptionMappingInterceptor from the interceptor stack if you really want to use the web.xml method.