Java 上传文件总结

1. 使用commons-fileupload.jar+commons-io.jar 上传

1 try {
 2             DiskFileItemFactory factory = new DiskFileItemFactory();
 3             factory.setSizeThreshold(1024 * 1024 * 10);
 4             factory.setRepository(new File(request.getRealPath("/")));
 5             System.out.println(">>>" + request.getParameter("file5"));
 6             ServletFileUpload upload = new ServletFileUpload(factory);
 7             upload.setSizeMax(1024 * 1024 * 10);
 8             List<FileItem> items = upload.parseRequest(request);
 9             for (FileItem item : items) {
10                 if (item.isFormField()) {
11                     String name = item.getFieldName();
12                     String value = item.getString("GBK");
13                     System.out.println(name + "-----" + value);
14                 } else {
15                     String fieldName = item.getFieldName();
16                     String fileName = item.getName();
17                     System.out.println("文件域名称:" + fieldName);
18                     System.out.println("文件名:" + fileName);
19                     System.out.println("文件类型:" + item.getContentType());
20                     FileOutputStream fos = new FileOutputStream(request
21                             .getRealPath("/")
22                             + fileName.substring(fileName.lastIndexOf("\\")));
23                     if(item.isInMemory()){
24                         fos.write(item.get());
25                     }else{
26                         InputStream is=item.getInputStream();
27                         byte[] buffer=new byte[1024];
28                         int len=0;
29                         while((len=is.read())>0){
30                             fos.write(buffer,0,len);
31                         }
32                         is.close();
33                         fos.close();
34                     }
35                 }
36             }
37         } catch (Exception e) {
38             System.out.println(e.getMessage());
39         }

 1 try {
 2             DiskFileItemFactory factory = new DiskFileItemFactory();
 3             factory.setSizeThreshold(1024 * 1024 * 10);
 4             factory.setRepository(new File(request.getRealPath("/")));
 5             System.out.println(">>>" + request.getParameter("file5"));
 6             ServletFileUpload upload = new ServletFileUpload(factory);
 7             upload.setSizeMax(1024 * 1024 * 10);
 8             List<FileItem> items = upload.parseRequest(request);
 9             for (FileItem item : items) {
10                 if (item.isFormField()) {
11                     String name = item.getFieldName();
12                     String value = item.getString("GBK");
13                     System.out.println(name + "-----" + value);
14                 } else {
15                     String fieldName = item.getFieldName();
16                     String fileName = item.getName();
17                     System.out.println("文件域名称:" + fieldName);
18                     System.out.println("文件名:" + fileName);
19                     System.out.println("文件类型:" + item.getContentType());
20                     FileOutputStream fos = new FileOutputStream(request
21                             .getRealPath("/")
22                             + fileName.substring(fileName.lastIndexOf("\\")));
23                     if(item.isInMemory()){
24                         fos.write(item.get());
25                     }else{
26                         InputStream is=item.getInputStream();
27                         byte[] buffer=new byte[1024];
28                         int len=0;
29                         while((len=is.read())>0){
30                             fos.write(buffer,0,len);
31                         }
32                         is.close();
33                         fos.close();
34                     }
35                 }
36             }
37         } catch (Exception e) {
38             System.out.println(e.getMessage());
39         }

 　 点击此处下载核心文件包 /Files/qingyuan/lib.rar

　　getFieldName()获取表单域的name属性值

　　getString(String encoding) 获得表单域的Value属性值,参数为编码集

　　getName()获得上传文件的名称

　　getContentType()获得上传文件的类型

　　get()获得上传文件的字节内容

(2) 使用COS上传

代码

 

　　使用COS上传文件需要使用cos.jar这个包，可以到Http://www.servlets.com/cos 这个网站下载

　　使用COS上传文件比Commons-fileupload 要方便许多，但是对中文支持不好，如果上传文件中有中文会出现乱码。所以建议使用Commons-fileupload.jar 上传。其实Struts2 中的 文件上传也是依赖这个包，只不过是进行了更进一步的封装。