文件下载

• IOUtils 的对应包

<dependency>
            <groupId>commons-io</groupId>
            <artifactId>commons-io</artifactId>
        </dependency>

需要关闭流的对象放在try（）内不用写关闭代码

@GetMapping("/{id}")
    public void download(@PathVariable String id, HttpServletRequest request, HttpServletResponse response) throws Exception {

        try (InputStream inputStream = new FileInputStream(new File(folder, id + ".txt"));
             OutputStream outputStream = response.getOutputStream();) {

            response.setContentType("application/x-download");
            response.addHeader("Content-Disposition", "attachment;filename=test.txt");

            IOUtils.copy(inputStream, outputStream);
            outputStream.flush();
        }

    }