common-fileupload 上传单个或者多个文件 示例
下载地址：google一下
该组件的介绍：google一下
想说的是：
该组件对中文支持良好，支持单文件与多文件的同时上传
主要类介绍
DiskFIleItemFactory类 ，该类创建FileItem对象的工厂类，开发人员可以在这个工厂类上配置上传过程中的
内存缓冲区大小和存放临时文件的目录，其中的repository属性主要指定上传文件保存的目录，sizeThreshold属性
则设置在内存中缓冲区大小
ServletFileUpload类 该类首先负责处理上传的文件的文件数据，最终完成文件上传的功能。在下面代码中，注意该
类使用时会抛出的一些异常。
FileItem类，该类包装上传表单中的各个请求属性，可以通过其中的isFormField属性访问方法识别某个FileItem类
对象实际代表的是普通表单成员域还是file类型的成员域
具体使用：
JSP页面： 注意form中标红色的部分，该方法以二进制流的方式来处理表单数据，并且把文件域指定的文件的内容也封装进了请求参数里
1
<%
@ page language
=
"
java
"
import
=
"
java.util.*
"
pageEncoding
=
"
utf-8
"
%>
2
<%
3
String path
=
request.getContextPath();
4
String basePath
=
request.getScheme()
+
"
://
"
+
request.getServerName()
+
"
:
"
+
request.getServerPort()
+
path
+
"
/
"
;
5
%>
6
7
<!
DOCTYPE HTML PUBLIC
"
-//W3C//DTD HTML 4.01 Transitional//EN
"
>
8
<
html
>
9
<
head
>
10
<
base href
=
"
<%=basePath%>
"
>
11
12
<
title
>
My JSP
'
filesUpload.jsp
'
starting page
</
title
>
13
14
</
head
>
15
16
<
body
>
17
<
form action
=
"
<%=basePath%>servlet/FileUploadServlet
"
enctype
="multipart/form-data"
method
=
"
post
"
>
18
<
input type
=
"
file
"
name
=
"
file1
"
><
br
>
19
<
input type
=
"
file
"
name
=
"
file2
"
><
br
>
20
<
input type
=
"
file
"
name
=
"
file3
"
><
br
>
21
<
input type
=
"
submit
"
>
22
</
form
>
23
</
body
>
24
</
html
>
25
Servlet代码
1
package
experiment4;
2
3
import
java.io.File;
4
import
java.io.IOException;
5
import
java.util.List;
6
7
import
javax.servlet.ServletException;
8
import
javax.servlet.http.HttpServlet;
9
import
javax.servlet.http.HttpServletRequest;
10
import
javax.servlet.http.HttpServletResponse;
11
12
import
org.apache.commons.fileupload.FileItem;
13
import
org.apache.commons.fileupload.FileUploadException;
14
import
org.apache.commons.fileupload.FileUploadBase.FileSizeLimitExceededException;
15
import
org.apache.commons.fileupload.disk.DiskFileItemFactory;
16
import
org.apache.commons.fileupload.servlet.ServletFileUpload;
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public
class
FileUploadServlet
extends
HttpServlet {
19
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public
void
doPost(HttpServletRequest request, HttpServletResponse response)
21
throws
ServletException, IOException {
22
request.setCharacterEncoding(
"
utf-8
"
);
//
防止中文名乱码
23
int
sizeThreshold
=
1024
*
6
;
//
缓存区大小
24
String basePath
=
this
.getServletContext().getRealPath(
"
/upload/
"
);
25
File repository
=
new
File(basePath);
//
缓存区目录
26
long
sizeMax
=
1024
*
1024
*
2
;
//
设置文件的大小为2M
27
final
String allowExtNames
=
"
jpg,gif,bmp,rar,rar,txt,docx
"
;
28
DiskFileItemFactory diskFileItemFactory
=
new
DiskFileItemFactory();
29
diskFileItemFactory.setRepository(repository);
30
diskFileItemFactory.setSizeThreshold(sizeThreshold);
31
ServletFileUpload servletFileUpload
=
new
ServletFileUpload(diskFileItemFactory);
32
servletFileUpload.setSizeMax(sizeMax);
33
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List
<
FileItem
>
fileItems
=
null
;
35
try
{
36
fileItems
=
servletFileUpload.parseRequest(request);
37
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for
(FileItem fileItem:fileItems){
39
long
size
=
0
;
40
String filePath
=
fileItem.getName();
41
System.out.println(filePath);
42
if
(filePath
==
null
||
filePath.trim().length()
==
0
)
43
continue
;
44
String fileName
=
filePath.substring(filePath.lastIndexOf(File.separator)
+
1
);
45
//
String fileName=String.valueOf(System.currentTimeMillis());
46
String extName
=
filePath.substring(filePath.lastIndexOf(
"
.
"
)
+
1
);
47
//
fileName+="."+extName;
48
if
(allowExtNames.indexOf(extName)
!=-
1
)
49
{
50
try
{
51
fileItem.write(
new
File(basePath
+
File.separator
+
fileName));
52
}
catch
(Exception e) {
53
e.printStackTrace();
54
}
55
}
56
else
{
57
throw
new
FileUploadException(
"
file type is not allowed
"
);
58
}
59
}
60
}
catch
(FileSizeLimitExceededException e){
61
System.out.println(
"
file size is not allowed
"
);
62
}
catch
(FileUploadException e1){
63
e1.printStackTrace();
64
}
65
66
67
}
68
69
}
70