java in the interceptor to intercept the object is moving Action calls. It provides a mechanism that allows developers to define an action performedBefore and after the execution of the code, Which can also prevent an action performed before execution, but also provided a way to extract the action part reusable. In AOP (Aspect-Oriented Programming) prior interceptor for a method or field is accessed, and the intercept is added before or after certain operations.
Interceptor main achievementHandlerInterceptor package under org.springframework.web.servletinterface.
preHandle for Handler method before performing this method.
postHandle for performing Handler after before returning ModelAndView.
afterCompletion for returning after ModelAndView , performs exception handling.
public class LoginInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest request,
HttpServletResponse response, Object handler) throws Exception {
// Handler之前执行此方法
return false;
}
@Override
public void postHandle(HttpServletRequest request,
HttpServletResponse response, Object handler,
ModelAndView modelAndView) throws Exception {
//执行Handler之后返回ModelAndView之前
// TODO Auto-generated method stub
}
@Override
public void afterCompletion(HttpServletRequest request,
HttpServletResponse response, Object handler, Exception ex)
throws Exception {
//返回ModelAndView之后，执行，异常处理。
// TODO Auto-generated method stub
}
}
Unfinished, continued.
