SpringMVC基本配置

1静态资源映射：

@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
    //addResourceLocations指的是文件放置的目录，addResourceHandler指的是对外暴露的访问路径
    registry.addResourceHandler("/assets/**").addResourceLocations("classpath:/assets/");
}

2拦截器配置：

定义拦截器：

public class DemoInterceptor extends HandlerInterceptorAdapter {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        long startTime=System.currentTimeMillis();
        request.setAttribute("startTime",startTime);
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        long startTime=(Long) request.getAttribute("startTime");
        request.removeAttribute("startTime");
        long endTime=System.currentTimeMillis();
        System.out.println("本次请求处理时间为："+new Long(endTime-startTime)+"ms");
        request.setAttribute("handlingTime",endTime-startTime);
    }
}

//匹配某些路径
@Override
public void addInterceptors(InterceptorRegistry registry) {
    registry.addInterceptor(demoInterceptor()).addPathPatterns("/**")
            .excludePathPatterns(
                    "/anno/*");
}

3@ControllerAdvice的使用（具体用法看注解）：

/**组合了Component注解
 * 将对控制器的全局配置放置在同一个位置
 * 注解了该注解的类可以使用@ExceptionHandler,@InitBinder,@ModelAttribute注解到方法上
 * 着对所有注解了@RequestMapping的控制器内的方法有效
 */
@ControllerAdvice
public class ExceptionHandlerAdvice {
    /**
     * 该注解用于全局处理控制器里的异常
     * @param exception
     * @param request
     * @return
     */
    @ExceptionHandler(value = Exception.class)
    public ModelAndView exception(Exception exception, WebRequest request){
        ModelAndView modelAndView=new ModelAndView("error");
        modelAndView.addObject("errorMessage",exception.getMessage());
        return modelAndView;
    }
    //可以让全局的@RequestMapping都能获取到此处设置的键值对
    @ModelAttribute
    public void addAttributes(Model model){
        model.addAttribute("msg","额外信息");
    }

    /**
     * 该注解用来设置WebDataBinder,WebDataBinder用来自动绑定前台请求参数到Model中,该方法会忽略request参数的id
     * @param webDataBinder
     */
    @InitBinder
    public void initBinder(WebDataBinder webDataBinder){
        webDataBinder.setDisallowedFields("id");
    }
}

测试例子：

@Controller
public class AdviceController {
    @RequestMapping("/advice")
    public String getSomething(@ModelAttribute("msg") String msg,DemoObj obj){
        throw new IllegalArgumentException("非常抱歉，参数有误/"+"来自@ModelAttribute:"+msg);
    }
}

4快捷的ViewController:

如果页面跳转无业务逻辑，只是简单的页面转向，可以通过重写addViewControllers来简化配置

@Override
public void addViewControllers(ViewControllerRegistry registry) {
    registry.addViewController("/index").setViewName("index");
}