Servlet上传图片

现在一做东西就少不了，上传这个，上传那个的，那么，我的构想是，servlet去上传到服务器，也就是你指定的文件夹里面，然后，在根据用户最终确定之后，在上传到数据库里面。

环境：web项目，包：commons-fileupload-1.2.1.jar，commons-io-1.4.jar

JAVA核心代码

//这是上传

package com.upload.action;

import java.io.File;
import java.io.IOException;
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.FileItemFactory;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

public class UploadServlet extends HttpServlet {

private static final long serialVersionUID = 2121906815386996943L;

@SuppressWarnings("unchecked")
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

//初始化 FileItemFactory
FileItemFactory factory = new DiskFileItemFactory();

// 初始化ServletFileUpload，可以说是一个封装好的的容器
  ServletFileUpload upload = new ServletFileUpload(factory);
  try {
   List<FileItem> list = upload.parseRequest(request);
   for (int i = 0; i < list.size(); i++) {
    FileItem fileItem = list.get(i);

//根据你想要的如XX.jpg等，来截取字符串
String name = fileItem.getName().substring(fileItem.getName().lastIndexOf("\") + 1);

//保存，别说你不知道是什么。。。。
    request.getSession().setAttribute(name, true);
    fileItem.write(new File("d:/upload/" + name));
    //这是上传图片的名字，如果只规定上传一次的话，那么直接拿这个name，如果比较多的话，那么。。。考虑中
    System.out.println(name);
   }
   //方法一、直接放入集合中，然后循环读出放入数据库（放一个图片就立即入库）
   //方法二、再写一个servlet，然后直接读出upload下的子文件夹，放入数据库（在确认这些图片的情况下，不进行改动的情况下再去入库）
   //考虑到可移植性的问题，那么采取方法二
  } catch (FileUploadException e) {
   e.printStackTrace();
  } catch (Exception e) {
   e.printStackTrace();
  }
}

}

//这是删除

package com.upload.action;

import java.io.File;
import java.io.IOException;

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

public class DeleteServlet extends HttpServlet {

private static final long serialVersionUID = -4097655768318294837L;

@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {
  request.setCharacterEncoding("utf-8");
  String fileName = request.getParameter("fileName");
  if(fileName != null) {
   boolean exist = false;
   try{
    exist = (Boolean) request.getSession().getAttribute(fileName);
   }catch(Exception e) {
    return;
   }
   if(exist) {
    File file = new File("d:/upload/" + fileName);
    if(file.exists()) {
     file.delete();
    }
    request.getSession().removeAttribute(fileName);
   }
  }
}

}

jsp页面可以说是HTML

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
    <title>My JSP 'index.jsp' starting page</title>
    <style type="text/css">
    .deleteImg {
      cursor: pointer;
    }
    #uploaddiv img {
      margin-left: 20px;
    }
    </style>
    <script type="text/javascript" src="js/jquery.js"></script>
    <script type="text/javascript" src="js/ajaxupload.3.5.js"></script>
    <script type="text/javascript">
    var uploadIndex = 1;
    $(function() {
       uploadIt();
       deleteFile();
    });
    function uploadIt() {

//最流行的jQuery，如果看不懂，那么 sorry，这里主要是上传。
      $(".uploadAndNext").click(function() {
    var uploadId = "#" + $(this).attr("id");
       var btn = $(this);
       new AjaxUpload( uploadId + "" , {
         action : "UploadServlet" ,
         onChange: function(file, extension){
           $(uploadId + "").parent().find("input")[0].value = file;
           $(uploadId + "").parent().find(".uploadAndOkImg").show().attr("src" , "images/spinner.gif");
           btn.attr("disabled" , "disabled");
         },

         onComplete: function(file, response) {
       $(uploadId + "").parent().find(".uploadAndOkImg").attr("src" , "images/ok.gif");
       $(uploadId + "").parent().find(".deleteImg").attr("src" , "images/delete.gif").show();
       uploadIndex++;
       $("#uploaddiv").append("<div><input type='text' /><button class='uploadAndNext' id='upload" + uploadIndex + "'>浏览</button><img src='' width='20px' height='20px' class='uploadAndOkImg' style='display:none'/><img src='' width='20px' height='20px' class='deleteImg' style='display:none' alt='删除'/></div>");
       uploadIt();
       deleteFile();
         }
       });
      });
    }
    function deleteFile() {
      $("#uploaddiv .deleteImg").click(function() {
        var fileName = $(this).parent().find("input").val();
        var thisObj = $(this);
        $.post("DeleteServlet" , {
         "fileName" : fileName
        },
         function(data) {
          thisObj.parent().remove();
         }
        );
       });
    }

//算了，还是提示一下，是jQuery的Ajax，OK?
    </script>

</head>

<body>
  <div id="uploaddiv">
   <div><input type="text" /><button class="uploadAndNext" id="upload1">浏览</button><img src="" width="20px" height="20px" class="uploadAndOkImg" style="display: none"/><img src="" width="20px" height="20px" class="deleteImg" style="display:none;" alt="删除"/></div>
  </div>
</body>

</html>
注：有点不好使，但是学习完之后，你可以自己创作。这只是个案例。

转：http://liuyang-1989xy.blog.163.com/blog/static/1687545732010111061145523/