springboot-项目获取resources下文件碰到的问题（classPath下找不到文件和文件名乱码）

项目是spring-boot + spring-cloud 并使用maven 管理依赖。在springboot+maven项目下怎么读取resources下的文件实现文件下载？

• 怎么获取resources目录下的文件？（相对路径）

方法一：

File sourceFile = ResourceUtils.getFile("classpath:templateFile/test.xlsx"); //这种方法在linux下无法工作

方法二：

Resource resource = new ClassPathResource("templateFile/test.xlsx"); File sourceFile = resource.getFile();

我使用的是第二种。

  @PostMapping("/downloadTemplateFile")
     public JSONData downloadTemplateFile(HttpServletResponse response) {
         String filePath = "templateFile/test.xlsx";
         Resource resource = new ClassPathResource(filePath);//用来读取resources下的文件
         InputStream is = null;
         BufferedInputStream bis = null;
         OutputStream os = null;
         try {
             File file = resource.getFile();
             if (!file.exists()) {
                 return new JSONData(false,"模板文件不存在");
             }
             is = new FileInputStream(file);
             os = response.getOutputStream();
             bis = new BufferedInputStream(is);
             //设置响应头信息
             response.setCharacterEncoding("UTF-8");
             this.response.setContentType("application/octet-stream; charset=UTF-8");
             StringBuffer contentDisposition = new StringBuffer("attachment; filename=\"");
             String fileName = new String(file.getName().getBytes(), "utf-8");
             contentDisposition.append(fileName).append("\"");
             this.response.setHeader("Content-disposition", contentDisposition.toString());
             //边读边写
             byte[] buffer = new byte[500];
             int i;
             while ((i = bis.read(buffer)) != -1) {
                 os.write(buffer, 0, i);
             }
             os.flush();
         } catch (FileNotFoundException e) {
             e.printStackTrace();
             return new JSONData(false,"模板文件不存在");
         } catch (IOException e) {
             e.printStackTrace();
         } finally {
             try {
                 if(os != null) os.close();
                 if(bis != null) bis.close();
                 if(is != null) is.close();
             } catch (IOException e) {
                 e.printStackTrace();
             }
         }
         return new JSONData("模板文件下载成功");
     }

高高兴兴的启动项目后发现还是找不到文件，错误日志：

 java.io.FileNotFoundException: class path resource [templateFile/test.xlsx] cannot be resolved to URL because it does not exist
     at org.springframework.core.io.ClassPathResource.getURL(ClassPathResource.java:195)
     at org.springframework.core.io.AbstractFileResolvingResource.getFile(AbstractFileResolvingResource.java:129)
     at com.citycloud.parking.support.controller.operate.OperateBusinessUserController.downloadTemplateFile(OperateBusinessUserController.java:215)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
     at java.lang.reflect.Method.invoke(Method.java:498)
     at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209)
     at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136)
     at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102)
     at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:877)
     at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:783)
     at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
     at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991)
     at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925)
     at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:974)
     at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:877)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:661)
     at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:851)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
     at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
     at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:158)
     at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:126)
     at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:111)
     at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)

因为我知道Resource resource = new ClassPathResource("templateFile/test.xlsx");就是到classPath*（注意这里有个*）下去找，然后就去项目本地的目录下找classPath下是否有这个文件（maven的classPath在 “target\classes”目录下），就发现并没有这个文件在。

后面仔细想想这是Maven项目啊，所以就找pom.xml文件去看看，突然想起：springboot的maven默认只会加载classPath同级目录下文件（配置那些），其他的需要配置<resources>标签：

 <build>
   <resources>
       <resource>
         <directory>src/main/java</directory>
         <includes>
           <include>**/*.properties</include>
           <include>**/*.xml</include>
         </includes>
         <!--是否替换资源中的属性-->
         <filtering>false</filtering>
       </resource>
       <resource>
         <directory>src/main/resources</directory>
         <includes>
           <include>**/*.properties</include>
           <include>**/*.xml</include>
           <include>**/*.yml</include>
           <include>**/Dockerfile</include>
           <include>**/*.xlsx</include>
         </includes>
         <!--是否替换资源中的属性-->
         <filtering>false</filtering>
       </resource>
   </resources>
 </build>

重新启动，再到classPath下看，发现有了这个文件了，同时也能获取了。如果文件名为中文的话就会出现乱码的情况。

• 怎么解决文件名中文乱码？

 Access-Control-Allow-Origin →*
 Access-Control-Allow-Credentials →true
 Access-Control-Allow-Headers →accessToken,Access-Control-Allow-Origin,Content-Type,X-Requested-With,accept,Origin,Access-Control-Request-Method,Access-Control-Request-Headers
 Access-Control-Allow-Methods →POST,GET,PUT,PATCH,DELETE,OPTIONS,HEAD
 Access-Control-Max-Age →360
 Content-disposition →attachment; filename="????????-??????????.xlsx"
 Content-Type →application/octet-stream;charset=UTF-8
 Transfer-Encoding →chunked
 Date →Fri, 19 Apr 2019 06:47:34 GMT

上面是使用postman测试中文乱码response响应头相关信息。

后面怎么改都乱码，然后我就试着到浏览器中请求试试，结果发现只是postman的原因，只要文件名编码跟返回内容编码一致（"Content-disposition"和“ContentType”）就行：

 this.response.setContentType("application/octet-stream; charset=iso-8859-1");
 StringBuffer contentDisposition = new StringBuffer("attachment; filename=\"");
 String fileName = file.getName();
 contentDisposition.append(fileName).append("\"");
 //设置文件名编码
 String contentDispositionStr = new String(contentDisposition.toString().getBytes(), "iso-8859-1");
 this.response.setHeader("Content-disposition", contentDispositionStr);

到此全部结束！