java组件fileupload文件上传demo
在我们的web开发中，很多的时候都需要把本机的一些文件上传到web服务器上面去。
如：一个BBS系统，当用户使用这是系统的时候，能把本机的一些图片，文档上传到服务器上面去。然后其他用户可以去下载这些文件，那么这样的话，我们可以自己编程实现文件的上传，但是更好的方式是使用一些已有的组件帮助我们实现这种上传功能。
常用的上传组件：
Apache的CommonsFileUpload
JavaZoom的UploadBean
jspSmartUpload
FileUpload下载地址：
http://commons.apache.org/fileupload/
下载：commons-fileupload-1.2.2-bin.zip 得到：commons-fileupload-1.2.2.jar
http://commons.apache.org/io/
下载：commons-io-1.4-bin.zip 得到：commons-io-1.4.jar
upload.jsp
代码；
<%@pagelanguage="java"contentType="text/html;charset=UTF-8"%>
<html>
<head>
<title>usingcommonsUploadtouploadfile</title>
</head>
<style>
*{font-family:"宋体";font-size:14px}
</style>
<body>
<palign="center">请您选择需要上传的文件</p>
<formid="form1"name="form1"method="post"action="servlet/fileServlet"enctype="multipart/form-data">
<tableborder="0"align="center">
<tr>
<td>上传人：</td>
<td>
<inputname="name"type="text"id="name"size="20"></td>
</tr>
<tr>
<td>上传文件：</td>
<td><inputname="file"type="file"size="20"></td>
</tr>
<tr>
<td></td><td>
<inputtype="submit"name="submit"value="提交">
<inputtype="reset"name="reset"value="重置">
</td>
</tr>
</table>
</form>
</body>
</html>
FileUploadServlet.java代码：
packagecom.b510.example;
importjava.io.File;
importjava.io.IOException;
importjava.util.*;
importjavax.servlet.ServletConfig;
importjavax.servlet.ServletContext;
importjavax.servlet.ServletException;
importjavax.servlet.http.HttpServlet;
importjavax.servlet.http.HttpServletRequest;
importjavax.servlet.http.HttpServletResponse;
importorg.apache.commons.fileupload.FileItem;
importorg.apache.commons.fileupload.FileUploadException;
importorg.apache.commons.fileupload.disk.DiskFileItemFactory;
importorg.apache.commons.fileupload.servlet.ServletFileUpload;
/**
*
*@authorXHW
*
*@date2011-7-26
*
*/
publicclassFileUploadServletextendsHttpServlet{
privatestaticfinallongserialVersionUID=-7744625344830285257L;
privateServletContextsc;
privateStringsavePath;
publicvoiddoGet(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
doPost(request,response);
}
publicvoidinit(ServletConfigconfig){
//在web.xml中设置的一个初始化参数
savePath=config.getInitParameter("savePath");
sc=config.getServletContext();
}
publicvoiddoPost(HttpServletRequestrequest,HttpServletResponseresponse)throwsServletException,IOException{
request.setCharacterEncoding("UTF-8");
DiskFileItemFactoryfactory=newDiskFileItemFactory();
ServletFileUploadupload=newServletFileUpload(factory);
try{
Listitems=upload.parseRequest(request);
Iteratoritr=items.iterator();
while(itr.hasNext()){
FileItemitem=(FileItem)itr.next();
if(item.isFormField()){
System.out.println("表单参数名:"+item.getFieldName()+"，表单参数值:"+item.getString("UTF-8"));
}else{
if(item.getName()!=null&&!item.getName().equals("")){
System.out.println("上传文件的大小:"+item.getSize());
System.out.println("上传文件的类型:"+item.getContentType());
//item.getName()返回上传文件在客户端的完整路径名称
System.out.println("上传文件的名称:"+item.getName());
FiletempFile=newFile(item.getName());
／／上传文件的保存路径
Filefile=newFile(sc.getRealPath("/")+savePath,tempFile.getName());
item.write(file);
request.setAttribute("upload.message","上传文件成功！");
}else{
request.setAttribute("upload.message","没有选择上传文件！");
}
}
}
}catch(FileUploadExceptione){
e.printStackTrace();
}catch(Exceptione){
e.printStackTrace();
request.setAttribute("upload.message","上传文件失败！");
}
request.getRequestDispatcher("/uploadResult.jsp").forward(request,response);
}
}
uploadResult.jsp代码：
<%@pagelanguage="java"import="java.util.*"pageEncoding="UTF-8"%>
<!DOCTYPEHTMLPUBLIC"-//W3C//DTDHTML4.01Transitional//EN">
<html>
<head>
<title>uploadResult</title>
<metahttp-equiv="pragma"content="no-cache">
<metahttp-equiv="cache-control"content="no-cache">
<metahttp-equiv="expires"content="0">
<metahttp-equiv="keywords"content="keyword1,keyword2,keyword3">
<metahttp-equiv="description"content="Thisismypage">
<!--
<linkrel="stylesheet"type="text/css"href="styles.css">
-->
</head>
<body>
${requestScope['upload.message']}
<ahref="/upload/uploadFile.jsp">上传文件</a>
</body>
</html>
web.xml
代码：
<?xmlversion="1.0"encoding="UTF-8"?> <web-appversion="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> <servlet> <description>ThisisthedescriptionofmyJ2EEcomponent</description> <display-name>ThisisthedisplaynameofmyJ2EEcomponent</display-name> <servlet-name>FileUploadServlet</servlet-name> <servlet-class>com.b510.example.FileUploadServlet</servlet-class> ＜！--设置初始化参数--＞ <init-param> <param-name>savePath</param-name> <param-value>uploads</param-value> </init-param> </servlet> <servlet-mapping> <servlet-name>FileUploadServlet</servlet-name> <url-pattern>/servlet/fileServlet</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file>index.jsp</welcome-file> <welcome-file>uploadFile.jsp</welcome-file> </welcome-file-list> </web-app>
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持毛票票。