springmvc实现文件的上传_factory.setsizethreshold-优快云博客

本文介绍了一个简单的文件上传功能实现过程，使用了commons-fileupload和commons-io库。通过HTML表单收集文件并提交至服务器，利用ServletFileUpload解析请求，再将文件写入指定位置。

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需要依赖的jar包，在pom.xml中添加commons-fileupload-1.2.1.jar、commons-io-2.0.jar（依赖包）

html页面代码如下：

<body>
 <form action="/projectms/test/simpleFileupload" method="post" enctype="multipart/form-data">  
    最简单的文件上传：<input type="file" name="fileupload"/>  
    描述：<input type="text" name="desc"/>  
    <input type="submit" value="submit"/>  
    </form>  
</body>

controller代码如下：

@RequestMapping("/simpleFileupload")
    public void  upload(HttpServletRequest request, HttpServletResponse response) throws IOException{


        DiskFileItemFactory factory=new DiskFileItemFactory();
        ServletFileUpload upload=new ServletFileUpload(factory);
        upload.setHeaderEncoding("utf-8");
        factory.setSizeThreshold(1024 * 500);//设置内存的临界值为500，如果超过则保存到/root/aaa目录下
        File linshiFile=new File("/root/aaa");
        factory.setRepository(linshiFile);
        upload.setSizeMax(1024 * 1024 * 5);
        try {
            List<FileItem> items=upload.parseRequest(request);
            for (FileItem item : items) {
                 if (item.isFormField()) {  
                        String name = item.getFieldName();  
                        String value = item.getString("utf-8");  
                        System.out.println(name + ": " + value);  

                }else {
                     String fileName = item.getName();  
                        long sizeInBytes = item.getSize();  
                        System.out.println(fileName);  
                        System.out.println(sizeInBytes);  

                        InputStream in = item.getInputStream();  
                        byte[] buffer = new byte[1024];  
                        int len = 0;  

                        fileName = "/root/bbb/" + fileName;//文件最终上传的位置  
                        System.out.println(fileName);  
                        OutputStream out = new FileOutputStream(fileName);  

                        while ((len = in.read(buffer)) != -1) {  
                            out.write(buffer, 0, len);  
                        }  

                        out.close();  
                        in.close();  
                    }  
                }  
        } catch (FileUploadException e) {
            e.printStackTrace();
        }

    }