我必须加上这个才能下载任何文件

    response.setContentType("application/octet-stream");
    response.setHeader("Content-Disposition",
            "attachment;filename="+"file.txt");

所有的代码:

@Controller
public class FileController {

@RequestMapping(value = "/file", method =RequestMethod.GET)
@ResponseBody
public FileSystemResource getFile(HttpServletResponse response) {

    final File file = new File("file.txt");
    response.setContentType("application/octet-stream");
    response.setHeader("Content-Disposition",
            "attachment;filename="+"file.txt");
    return new FileSystemResource(file);
 }
}

您应该能够直接在响应上写入文件。类似的

response.setContentType("application/pdf");      
response.setHeader("Content-Disposition", "attachment; filename=\"somefile.pdf\""); 

然后在response.getOutputStream()上将该文件写入二进制流。记得在最后执行response.flush()，这样就可以了。

我能够通过使用Spring的ResourceHttpMessageConverter中的内置支持来进行流处理。如果可以确定mime类型，这将设置内容长度和内容类型

@RequestMapping(value = "/files/{file_name}", method = RequestMethod.GET)
@ResponseBody
public FileSystemResource getFile(@PathVariable("file_name") String fileName) {
    return new FileSystemResource(myService.getFileFor(fileName)); 
}

我必须加上这个才能下载任何文件

    response.setContentType("application/octet-stream");
    response.setHeader("Content-Disposition",
            "attachment;filename="+"file.txt");

所有的代码:

@Controller
public class FileController {

@RequestMapping(value = "/file", method =RequestMethod.GET)
@ResponseBody
public FileSystemResource getFile(HttpServletResponse response) {

    final File file = new File("file.txt");
    response.setContentType("application/octet-stream");
    response.setHeader("Content-Disposition",
            "attachment;filename="+"file.txt");
    return new FileSystemResource(file);
 }
}

如下图所示

@RequestMapping(value = "/download", method = RequestMethod.GET)
public void getFile(HttpServletResponse response) {
    try {
        DefaultResourceLoader loader = new DefaultResourceLoader();
        InputStream is = loader.getResource("classpath:META-INF/resources/Accepted.pdf").getInputStream();
        IOUtils.copy(is, response.getOutputStream());
        response.setHeader("Content-Disposition", "attachment; filename=Accepted.pdf");
        response.flushBuffer();
    } catch (IOException ex) {
        throw new RuntimeException("IOError writing file to output stream");
    }
}

您可以在这里显示PDF或下载示例

下面的解决方案对我很有效

    @RequestMapping(value="/download")
    public void getLogFile(HttpSession session,HttpServletResponse response) throws Exception {
        try {

            String fileName="archivo demo.pdf";
            String filePathToBeServed = "C:\\software\\Tomcat 7.0\\tmpFiles\\";
            File fileToDownload = new File(filePathToBeServed+fileName);

            InputStream inputStream = new FileInputStream(fileToDownload);
            response.setContentType("application/force-download");
            response.setHeader("Content-Disposition", "attachment; filename="+fileName); 
            IOUtils.copy(inputStream, response.getOutputStream());
            response.flushBuffer();
            inputStream.close();
        } catch (Exception exception){
            System.out.println(exception.getMessage());
        }

    }