常用Web文件上传方式 Cos上传文件

    关于上传组件,据网上专家介绍,在上传文件时Cos的性能最好,其次时FileUpload,最后为JspSmartUpload这个组件.

 Cos上传的代码如下:

通过MultipartRequest实现文件的上传的信息进行封裝形成 .具体情况帮助文档.

package com.vnvtrip;

import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Enumeration;

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

import com.oreilly.servlet.MultipartRequest;
/**
 *
 * @author longgangbai
 *
 */
public class FileUploadServlet extends HttpServlet {

 private static String DEFAULT_COS_UPLOAD_DIR = "C://upload";
 private static String DEFAULT_FILE_ENCODING_CHARSET = "UTF-8";

 /**
  * Constructor of the object.
  */
 public FileUploadServlet() {
  super();
 }

 /**
  * Destruction of the servlet. <br>
  */
 public void destroy() {
  super.destroy(); // Just puts "destroy" string in log
 }

 /**
  *
  * 采用Cos上传文件的主要方法类
  */
 @SuppressWarnings("unchecked")
 public void service(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {
  PrintWriter out = response.getWriter();
  // 存儲在创建上传文件目录
  File file = new File(DEFAULT_COS_UPLOAD_DIR);
  if (!file.isDirectory()) {
   file.mkdirs();
  }

  // 上传文件总的大小
  int maxPostSize = 3 * 5 * 1024 * 1024;
  // response的编码为"gb2312",同时采用缺省的文件名冲突解决策略,实现上传
  // 第一个参数为HttpServletRequest 第二参数: maxPostSize 上传文件大小 第三个目录上传文件目录
  MultipartRequest multi = new MultipartRequest(request,
    DEFAULT_COS_UPLOAD_DIR, maxPostSize,
    DEFAULT_FILE_ENCODING_CHARSET);
  // 输出反馈信息
  Enumeration files = multi.getFileNames();
  // 遍历上传的文件
  while (files.hasMoreElements()) {
   // 获取上传文件的對應的名称
   String name = (String) files.nextElement();
   System.out.println("name" + name);
   // 获取名称對應的文件
   File f = multi.getFile(name);
   if (f != null) {
    // 获取對應名称文件的路徑信息
    String fileName = multi.getFilesystemName(name);
    // 进行相关的数据库日志等业务操作
    // ......
    String lastFileName = DEFAULT_FILE_ENCODING_CHARSET
      + File.separator + fileName;
    out.println("上传的文件:" + lastFileName);
   }
  }
 }

 public void init() throws ServletException {
 }

}

 

web.xml配置如下:

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="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>This is the description of my J2EE component</description>
    <display-name>This is the display name of my J2EE component</display-name>
    <servlet-name>fileUpload</servlet-name>
    <servlet-class>com.vnvtrip.FileUploadServlet</servlet-class>
  </servlet>

  <servlet-mapping>
    <servlet-name>fileUpload</servlet-name>
    <url-pattern>/fileUpload</url-pattern>
  </servlet-mapping>
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
</web-app>

html上传的註意點同FileUpload上传(忽略).