The SSH project encountered a problem where the interceptor could not inject the service

Configuring Applicationcontext.xml, adding a properity property to a custom interceptor is a biz that keeps the null pointer exception at run time, and the output biz is always null, is it curious that the interceptor cannot be injected?

--then tried a direct instantiation of biz, the result is ... Null pointer ... I really don't understand ... Can't do it. Finally, the data is taken out early, there is a session, in the interceptor first from the session to take out the data, and then .... In making a judgment intercept ~ ~

Does anyone know how to inject biz or DAO into an interceptor?

The SSH project encountered a problem where the interceptor could not inject the service