SpringMVC拦截器

注意：拦截器是框架中的技术，拦截的是controller中执行的方法

springmvc配置文件：

        <!-- 配置SpringMVC拦截器 -->
	<mvc:interceptors>
		<!-- 一个拦截器 -->
		<mvc:interceptor>
			<!-- 要拦截的配置 -->
			<mvc:mapping path="/*" />
			<!-- 设置不拦截的配置 -->
			<mvc:exclude-mapping path="/login.do" />
			<!-- 配置拦截器 -->
			<bean class="com.zhengqing.controller.MyInterceptor" />
		</mvc:interceptor>
	</mvc:interceptors>

自定义类继承HandlerInterceptor：

public class MyInterceptor implements HandlerInterceptor {
	
	@Override
	public boolean preHandle(HttpServletRequest req, HttpServletResponse resp, Object object) throws Exception {
		System.out.println("===拦截===");
		return true;//false为拦截，true为放行
	}

	@Override
	public void postHandle(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, ModelAndView arg3) throws Exception {
		System.out.println("===处理完请求之后===");
	}

	@Override
	public void afterCompletion(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, Exception arg3) throws Exception {
		System.out.println("===DispatcherServlet完结之后调用===");
	}
	
}