文件上传之Servlet

导包 commons-fileupload-1.3.1.jar commons-io-2.2.jar

        

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;


public class UploadHandleServlet extends HttpServlet {

	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		
		String savePath=this.getServletContext().getRealPath("/WEB-INF/upload/");
		File file=new File(savePath);
		if(!file.exists()&&!file.isDirectory()){
			System.out.println(savePath+"目录不存在，需要创建");
			
			//创建目录
			file.mkdirs();
		}
		
		//消息提示
		String message="";
		
		//创建DiskFileItemFactory工厂
		DiskFileItemFactory factory=new DiskFileItemFactory();
		//创建一个文件上传解析器
		ServletFileUpload upload=new ServletFileUpload(factory);
		//解决文件上传乱码问题
		upload.setHeaderEncoding("UTF-8");
		
		if(!ServletFileUpload.isMultipartContent(request)){
			//按照传统方面获取数据
			return;
		}
		
		try {
			//使用ServletFileUpload解析器解析数据，返回来的是一个List<FileItem>集合,每一个FileItem对应一个表单输出
			List<FileItem> list=upload.parseRequest(request);
		
			for (FileItem item : list) {
				
				if(item.isFormField()){
					String name=item.getFieldName();
					String value=item.getString("UTF-8");
					System.out.println(name+"="+value);
				}else{
					String filename=item.getName();
					System.out.println(filename);
					if(filename==null||filename.trim().equals("")){
						continue;
					}
					//处理获取到的上传文件的文件名的路径部分，只保留文件名部分
					filename=filename.substring(filename.lastIndexOf("\")+1);
					//获取item文件上传输入流
					InputStream in=item.getInputStream();
					
					//创建一个文件输出流
					FileOutputStream out=new FileOutputStream(savePath+"\"+filename);
					
					byte[] buffer=new byte[1024];
					
					int len=0;
					
					while((len=in.read(buffer))>0){
						out.write(buffer,0,len);
					}
					in.close();
					out.close();
					item.delete();
				
					message="文件上传成功";
				}
			}
		} catch (FileUploadException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
		request.setAttribute("message", message);
		request.getRequestDispatcher("/message.jsp").forward(request, response);
		
	}

	
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}

}

　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　jsp页面

<%@ page language="java" pageEncoding="UTF-8"%>
  <!DOCTYPE HTML>
  <html>
    <head>
      <title>文件上传</title>
    </head>
    
    <body>
      <form action="${pageContext.request.contextPath}/UploadHandleServlet" enctype="multipart/form-data" method="post">
         上传用户：<input type="text" name="username"><br/>
         上传文件1：<input type="file" name="file1"><br/>

         <input type="submit" value="提交">
   </form>

</body>

</html>

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>成功页面</title>
</head>
<body>
${message}
</body>
</html>