Spring 拦截器（Interceptor )的使用

执行位置

在请求到达DispacherServlet后，在DispacherServlet调用某个Controller类执行

拦截器用途：

对用户是否登录做出判断
拦截产生的日志信息
拦截器的实现

public class MyInterceptor implements HandlerInterceptor {

	@Override
	public void afterCompletion(HttpServletRequest request, 
			HttpServletResponse response, Object handler, Exception ex)
			throws Exception {
		
	}

	@Override
	public void postHandle(HttpServletRequest request, 
			HttpServletResponse response, Object handler,
			ModelAndView modelAndView) throws Exception {
		
	}

	@Override
	public boolean preHandle(HttpServletRequest request, 
			HttpServletResponse response, Object handler)
			throws Exception {
		//return false 则进行拦截，不继续往下调用
		return true;
	}
	
}

实现HandlerInterceptor中各方法的运行顺序以及关系

拦截器的配置
mvc:mapping path=“” 需要过滤的路径
mvc:exclude-mapping path=""排除路径
bean class=“实现HandlerInterceptor类的全名” 进行这个过滤的类

 <mvc:interceptors>
     <mvc:interceptor>
            <mvc:mapping path="/*"/>
            <mvc:exclude-mapping path="/login/*"/>
            <bean class="实现HandlerInterceptor类的全名" />
    </mvc:interceptor>
</mvc:interceptors>