Question

springmvc的静态资源为什么被拦截

Answer 1

"mvc:annotation-driven" 的前缀 "mvc"未绑定
办法：这是我在spring-servlet.xml文件里使用<mvc>开头的标签时，忘记引入了命名空间。在xml的beans里面加入如下代码即可
xmlns:mvc="http://www.springframework.org/schema/mvc"
http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd

静态文件访问,主要是让DispatcherServlet不拦截以下静态资源
<mvc:annotation-driven />
<mvc:resources location="/image/" mapping="/image/**"/>
<mvc:resources location="/css/" mapping="/css/**"/>
<mvc:resources location="/js/" mapping="/js/**"/>

<!-- 启动扫描所有的controller -->
<context:component-scan base-package="com.peidw.web"/>
<mvc:annotation-driven/>

<!-- 对特定路径拦截-->
<mvc:interceptors>
<mvc:interceptor>
<mvc:mapping path="/user/MyHome"/>
<mvc:mapping path="/um/*"/>
<bean class="com.peidw.web.interceptor.MyInterceptor"></bean>
</mvc:interceptor>
</mvc:interceptors>

在java代码里实现拦截
package com.peidw.web.interceptors;

import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.log4j.*;
/**
* Created by peidw on 2015/3/6.
*/

@Component
public class HelloInterceptor implements HandlerInterceptor{
private static Logger logger=Logger.getLogger(HelloInterceptor.class);

@Override
public boolean preHandle(HttpServletRequest httpServletRequest,
HttpServletResponse httpServletResponse, Object o) throws Exception {
logger.info("执行Action前先判断权限");
return true;
}

@Override
public void postHandle(HttpServletRequest httpServletRequest,
HttpServletResponse httpServletResponse, Object o, ModelAndView
modelAndView) throws Exception {
logger.info("生成视图前，可以改model和视图");
}

@Override
public void afterCompletion(HttpServletRequest httpServletRequest,
HttpServletResponse httpServletResponse, Object o, Exception e) throws
Exception {
logger.info("生成视图前，可以改model和视图");
}
}

package com.peidw.web;

import com.peidw.web.interceptors.HelloInterceptor;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

/**
* Created by peidw on 2015/3/6.
*/

@Configuration
@EnableWebMvc
public class WebApplicationConfig extends WebMvcConfigurerAdapter {
@Override
public void addInterceptors(InterceptorRegistry registry) {
registry.addInterceptor(new HelloInterceptor()).addPathPatterns("/hello");;

}
}

<!-- 全局拦截 -->
<mvc:interceptors>
<bean class="com.peidw.web.interceptor.MyInterceptor"></bean>
</mvc:interceptors>

一些常用注解
@Autowired和@Qualifier 自动注入[根据类型注入]
@Autowired 可以对成员变量、方法以及构造函数进行注释，
@Qualifier 的标注对象是成员变量、方法入参、构造函数入参。
ps：两者结合使用相当于@Resourcede效果。
@Resource 自动注入[根据名称注入],可写参数name=""
@Controller 表示控制器
@Service 表示业务处理层[一般在serviceImpl]
@Repository 表示持久层[一般在daoImpl]
@Component 当你的类不清楚是哪一层的时候使用该注解
@ResponseBody 异步返回数据类型为json
@RequestMapping 路径，请求类型等设置
@InitBinder 数据绑定
@RequestBody、@ModeleAttributes、@SessionAttributes等