Apache的FileUpload组件(转)

1>首先创建一个HTML页面。注意，凡是要上载文件的表单都必须设置enctype属性，且属性的值必须是multipart/form-data，同时请求方法必须是POST.
<form action="fileuploaddemo.jsp"  method="post" enctype="multipart/form-data">
 
2>commons-fileupload-1.1.jar和commons-io-1.1.jar 两个包都要引入，
因为在parseRequest(request)的类有关继承于DiskFileItem类。

3>示例
1．示例1。    DiskFileUpload类会对mulipart类的表单中的所有字段进行处理，不只是file字段。getName（）得到文件名，getString（）得到表单数据内容，isFormField（）可判断是否为普通的表单项。
demo1.html<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GB18030">
<title>File upload</title>
</head>
<body>
//必须是multipart的表单数据。
<form action="demo1.jsp" method="post" enctype="multipart/form-data">
   Your name:<br>
   <input size="15"><br>
   File:<br>
   <input><br><br>
   <input value="Commit">
</form>
</body>
</html>demo1.jsp <%@ page contentType="text/html; charset=GB18030"
     pageEncoding="GB18030"%>
<%@ page import="org.apache.commons.fileupload.*"%>
<%@ page import="java.util.*"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<%
   boolean isMultipart=FileUpload.isMultipartContent(request);//检查输入请求是否为multipart表单数据。
   if(isMultipart==true){
      DiskFileUpload upload=new DiskFileUpload();//为该请求创建一个DiskFileUpload对象，通过它来解析请求。执行解析后，所有的表单项目都保存在一个List中。
      List items=upload.parseRequest(request);
      Iterator itr=items.iterator();
      while(itr.hasNext()){
            FileItem item=(FileItem)itr.next();
           //检查当前项目是普通表单项目还是上传文件。
            if(item.isFormField()){//如果是普通表单项目，显示表单内容。
                 String fieldName=item.getFieldName();
                 if(fieldName.equals("name")) //对应demo1.html中type="text"
                 out.println("the field name is"+ item.getString());//显示表单内容。
                 out.println("<br>");
             }
             else{//如果是上传文件，显示文件名。
               out.println("the upload fielname is"+item.getName());
              out.println("<br>");
            }
     }
}
else{
    out.println("the enctype must be multipart/form-data");
}
%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GB18030">
<title>File upload</title>
</head>
<body>
</body>
</html>2．示例2。    上传两个文件到指定的目录。
demo2.html<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GB18030">
<title>File upload</title>
</head>
<body>
<form action="demo2.jsp" method="post" enctype="multipart/form-data">
   File1:<br>
   <input><br>
   File2:<br>
   <input><br><br>
   <input value="Commit">
</form>
</body>
</html>demo2.jsp <%@ page contentType="text/html; charset=GB18030"
     pageEncoding="GB18030"%>
<%@ page import="org.apache.commons.fileupload.*"%>
<%@ page import="java.util.*"%>
<%@ page import="java.io.*"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<%String uploadPath="D:\\Dvp\\workspace4Lomboz\\Test4Jsp\\uploadfiles";
      boolean isMultipart=FileUpload.isMultipartContent(request);
      if(isMultipart==true){
           try{
                DiskFileUpload upload=new DiskFileUpload();
                List items=upload.parseRequest(request);//得到所有的文件
                Iterator itr=items.iterator();
                while(itr.hasNext()){//依次处理每个文件
                     FileItem item=(FileItem)itr.next();
                     String fileName=item.getName();//获得文件名，包括路径
                     if(fileName!=null){
                         File fullFile=new File(item.getName());
                         File savedFile=new File(uploadPath,fullFile.getName());
                         item.write(savedFile);
                      }
                }
               out.println("upload succeed");
         }
         catch(Exception e){
             e.printStackTrace();
          }
   }
   else{
         out.println("the enctype must be multipart/form-data");
   }
%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GB18030">
<title>File upload</title>
</head>
<body>
</body>
</html>3．示例3。    上传一个文件到指定的目录，并限定文件大小。
demo3.html<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GB18030">
<title>File upload</title>
</head>
<body>
<form action="demo3.jsp" method="post" enctype="multipart/form-data">
   File:<br>
   <input><br><br>
   <input value="Commit">
</form>
</body>
</html>demo3.jsp <%@ page contentType="text/html; charset=GB18030"
     pageEncoding="GB18030"%>
<%@ page import="org.apache.commons.fileupload.*"%>
<%@ page import="java.util.*"%>
<%@ page import="java.io.*"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<%File uploadPath=new File("D:\\upload");//上传文件目录
       if(!uploadPath.exists()){
            uploadPath.mkdirs();
        }
        String tempPath="d:\\upload\\temp\\"; // 临时文件目录
        File tempPathFile=new File("d:\\upload\\temp");
        if(!tempPathFile.exists()){
            tempPathFile.mkdirs();
       }
       try{
           DiskFileUpload fu=new DiskFileUpload();
           fu.setSizeMax(4194304); // 设置最大文件尺寸，这里是4MB
           fu.setSizeThreshold(4096); // 设置缓冲区大小，这里是4kb
           fu.setRepositoryPath(tempPath);//设置缓冲区目录
           List fileItems=fu.parseRequest(request);
           Iterator i=fileItems.iterator();
           while(i.hasNext()){
              FileItem fi=(FileItem)i.next();
              String fileName=fi.getName();
              if(fileName!=null){
                   File fullFile=new File(fi.getName());
                   File savedFile=new File(uploadPath,fullFile.getName());
                   fi.write(savedFile);
              }
         }
         out.println("upload succeed");
     }
     catch(Exception e){
         e.printStackTrace();
     }
%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GB18030">
<title>File upload</title>
</head>
<body>
</body>
</html>4．示例4。    利用Servlet来实现文件上传。
Upload.javapackage com.zj.sample; import java.io.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
import org.apache.commons.fileupload.*; public class Upload extends HttpServlet {
    private String uploadPath="D:\\upload\\"; // 上传文件的目录
    private String tempPath= "d:\\upload\\temp\\"; // 临时文件目录
    public void doPost(HttpServletRequest request, HttpServletResponse response)
      throws IOException, ServletException {
       try {
            DiskFileUpload fu = new DiskFileUpload();
            fu.setSizeMax(4194304);
            fu.setSizeThreshold(4096);
            fu.setRepositoryPath(tempPath);
            List fileItems = fu.parseRequest(request);
            Iterator i = fileItems.iterator();
            while (i.hasNext()) {
                 FileItem fi=(FileItem)i.next();
                 String fileName=fi.getName();
                 if(fileName!=null){
                      File fullFile=new File(fi.getName());
                      File savedFile=new File(uploadPath,fullFile.getName());
                      fi.write(savedFile);
                 }
            }
            System.out.println("upload succeed");
        }
        catch (Exception e) {
             // 可以跳转出错页面
             e.printStackTrace();
        }
   } public void init() throws ServletException {
       File uploadPath = new File("D:\\upload");
       if (!uploadPath.exists()) {
            uploadPath.mkdirs();
       }
       File tempPathFile = new File("d:\\upload\\temp");
       if (!tempPathFile.exists()) {
           tempPathFile.mkdirs();
       }
    }
}demo4.html <html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GB18030">
<title>File upload</title>
</head>
<body>
// action="fileupload"对应web.xml中<servlet-mapping>中<url-pattern>的设置。
<form action="fileupload" method="post" enctype="multipart/form-data">
   File:<br>
   <input><br><br>
   <input value="Commit">
</form>
</body>
</html>
web.xml     <servlet>
       <servlet-name>Upload</servlet-name>
       <servlet-class>com.zj.sample.Upload</servlet-class>
     </servlet>     <servlet-mapping>
      <servlet-name>Upload</servlet-name>
      <url-pattern>/fileupload</url-pattern>

 

posted @ 2010-04-16 17:28  Aotema  阅读(1263)  评论(0)  编辑  收藏  举报