Java Web开发之文件上传

文件上传有SmartUpload、Apache的Commons fileupload.我们今天介绍Commons fileupload的用法。

1.commons-fileupload-1.3.1.jar

下载地址：http://pan.baidu.com/s/1kVtYMzH

2.web.xml

 1 
 2   
 3     UploadServlet
 4     com.servlet.UploadServlet
 5     
 6     filePath
 7     F:\myeclipse\Workspaces\King\WebRoot\uploadfile\
 8     
 9   
10   
11   
12     UploadServlet
13     /servlet/UploadServlet
14   

3.UploadFile.jsp

 1 

4.servlet

  1 package com.servlet;
  2 
  3 import java.io.File;
  4 import java.io.FileOutputStream;
  5 import java.io.IOException;
  6 import java.io.InputStream;
  7 import java.io.InputStreamReader;
  8 import java.io.OutputStream;
  9 import java.io.PrintWriter;
 10 import java.util.List;
 11 
 12 import javax.servlet.ServletException;
 13 import javax.servlet.http.HttpServlet;
 14 import javax.servlet.http.HttpServletRequest;
 15 import javax.servlet.http.HttpServletResponse;
 16 
 17 import org.apache.commons.fileupload.DiskFileUpload;
 18 import org.apache.commons.fileupload.FileItem;
 19 import org.apache.commons.fileupload.FileUploadException;
 20 
 21 import sun.swing.FilePane;
 22 
 23 public class UploadServlet extends HttpServlet {
 24 
 25     private String filePath;
 26 
 27 
 28     /**
 29      * Destruction of the servlet. 
 30      */
 31     public void destroy() {
 32         super.destroy(); // Just puts "destroy" string in log
 33         // Put your code here
 34     }
 35 
 36     
 37     public void doGet(HttpServletRequest request, HttpServletResponse response)
 38             throws ServletException, IOException {
 39 
 40         response.setCharacterEncoding("UTF-8");
 41         response.getWriter().println("请以POST方式上传文件");
 42     }
 43 
 44     
 45     public void doPost(HttpServletRequest request, HttpServletResponse response)
 46             throws ServletException, IOException {
 47         File file1 = null, file2 = null;
 48         String description1 = null, description2 = null;
 49         response.setCharacterEncoding("UTF-8");
 50         request.setCharacterEncoding("UTF-8");
 51         response.setContentType("text/html");
 52         PrintWriter out = response.getWriter();
 53         
 54         DiskFileUpload diskFileUpload = new DiskFileUpload();//解析request
 55         
 56         try {
 57             List fileList = diskFileUpload.parseRequest(request);//将结果放置到List中
 58             out.println("遍历所有的FileItem...");
 59             this.log("遍历所有的FileItem...");
 60             for(FileItem fileItem : fileList){
 61                 if(fileItem.isFormField()){//如果是文本域
 62                     if("description1".equals(fileItem.getFieldName())){
 63                         out.println("遍历到description1...");
 64                         description1 = new String(fileItem.getString().getBytes(),"UTF-8");
 65                     }
 66                     if("description2".equals(fileItem.getFieldName())){
 67                         out.println("遍历到description2...");
 68                         description2 = new String(fileItem.getString().getBytes(),"UTF-8");
 69                     }
 70                 }else{//否则为文件域
 71                     if("file1".equals(fileItem.getFieldName())){
 72                         File remoteFile = new File(new String(fileItem.getName().getBytes(),"UTF-8"));
 73                         out.println("遍历到file1...");
 74                         out.println("客户端文件位置："+remoteFile.getAbsolutePath()+"");
 75                         //服务器端文件，放在uploadfile文件夹下
 76                         file1 = new File(filePath,remoteFile.getName());
 77                         file1.getParentFile().mkdirs();//创建文件夹路径
 78                         file1.createNewFile();//创建新文件
 79                         InputStream ins = fileItem.getInputStream();//FileItem的内容
 80                         OutputStream ous = new FileOutputStream(file1);//输出到文件中
 81                         try{
 82                             byte[] buffer = new byte[1024];//字节缓存
 83                             int len = 0;//实际缓存长度
 84                             while((len=ins.read(buffer)) > -1){//循环读入缓存
 85                                 ous.write(buffer,0,len);
 86                             }
 87                             out.println("已保存文件"+file1.getAbsolutePath()+"");
 88                         }
 89                         finally{
 90                             ous.close();
 91                             ins.close();
 92                         }
 93                     }
 94                     if("file2".equals(fileItem.getFieldName())){
 95                         File remoteFile = new File(new String(fileItem.getName().getBytes(),"UTF-8"));
 96                         out.println("遍历到file2...");
 97                         out.println("客户端文件位置："+remoteFile.getAbsolutePath()+"");
 98                         //服务器端文件，放在uploadfile文件夹下
 99                         file2 = new File(filePath,remoteFile.getName());
100                         file2.getParentFile().mkdirs();//创建文件夹路径
101                         file2.createNewFile();//创建新文件
102                         InputStream ins = fileItem.getInputStream();//FileItem的内容
103                         OutputStream ous = new FileOutputStream(file2);//输出到文件中
104                         try{
105                             byte[] buffer = new byte[1024];//字节缓存
106                             int len = 0;//实际缓存长度
107                             while((len=ins.read(buffer)) > -1){//循环读入缓存
108                                 ous.write(buffer,0,len);
109                             }
110                             out.println("已保存文件"+file2.getAbsolutePath()+"");
111                         }
112                         finally{
113                             ous.close();
114                             ins.close();
115                         }
116                     }
117                 }
118             }
119             out.println("Request 解析完毕");
120         } catch (FileUploadException e) {
121             // TODO 自动生成的 catch 块
122             out.println("");
123             out.println("");
124             out.println("");
125             out.println("");
126             
127             if(file1 != null){
128                 out.println("");
129                 out.println(" file1;");
130                 out.println(" 131                         file1.getName()+"'target=_blank>"+file1.getName()+"");
132                 out.println("");
133                 out.println("");
134             }
135             if(file2 != null){
136                 out.println("");
137                 out.println(" file2;");
138                 out.println(" 139                         file2.getName()+"'target=_blank>"+file2.getName()+"");
140                 out.println("");
141                 out.println("");
142             }
143             out.println("");
144             out.println(" description1:");
145             out.println(" ");
146             out.println(description1);
147             out.println("");
148             out.println("");
149             
150             out.println("");
151             out.println(" description2:");
152             out.println(" ");
153             out.println(description2);
154             out.println("");
155             out.println("");
156             
157             out.println("");
158             out.println("");
159             out.flush();
160             out.close();
161         }
162         
163     }
164 
165     public String getServletInfo() {
166         return "This is my default servlet created by Eclipse";
167     }
168 
169     
170     public void init() throws ServletException {
171         // Put your code here
172         filePath = getServletConfig().getInitParameter("filePath");
173     }
174 
175 }

6.