以下是获取servletContext:

import javax.servlet.ServletContext;import org.springframework.web.context.ContextLoader;import org.springframework.web.context.WebApplicationContext;/** * ServletContext辅助类。提供springmvc获取servletContext对象及项目真实路径的静态方法 * @author Administrator * */public class ServletContextUtils { private ServletContextUtils() { } /** * 获取ServletContext对象 * @return ServletContext对象 */ public static ServletContext getServletContext() { WebApplicationContext webApplicationContext = ContextLoader.getCurrentWebApplicationContext(); ServletContext context = webApplicationContext.getServletContext(); return context; } /** * 根据folder获取文件的真实路径 * @param folder 要获取文件夹的真实路径 * @return folder的真实路径 */ public static String getRealPath(String folder) { ServletContext context = getServletContext(); String path = context.getRealPath(folder); return path; }}

以下是文件下载代码：

@RequestMapping("/{filename}") public ResponseEntity<byte[]> download(@PathVariable String filename) throws IOException { ResponseEntity<byte[]> entity = null; try { HttpHeaders headers = new HttpHeaders(); String pathname = getFilepath(filename); File file = new File(pathname); headers.setContentType(MediaType.APPLICATION_OCTET_STREAM); entity = new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file), headers, HttpStatus.CREATED); return entity; } catch (IOException e) { logger.error(e.getMessage()); throw e; } } private String getFilepath(String filename) { String pathname = ServletContextUtils.getRealPath("/file") + "\\" + filename + ".txt"; return pathname; }

springmvc4 以上版本已经实现与servlet的低耦合，不知道为什么很多人写代码用的也是springMVC4或者5，仍然在使用httprequest。