jsp上传文件到服务器-CFANZ编程社区

准备

我使用环境是windows10，IDEA。

需要导入两个jar包，commons-io-2.6.jar和commons-fileupload-1.3.3.jar（点击即可下载），下载后解压，找到解压文件夹下的对应的两个jar包，然后复制到自己项目下的 WEB-INF/lib/目录下（也可以放在其他地方），最后导入两个包到项目：

jsp上传文件到服务器_apache

代码

前台jsp代码，注意form表单 action属性值为servlet的url，必须有 enctype="multipart/form-data" ，否则文件传输失败

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>资料</title>
</head>
<body>
    <div class="bigContainer">

            <div>
                <form action="/ServletUpload" method="post" enctype="multipart/form-data">
                    <input type="file" name="file">
                    <button type="submit">OK</button>
                </form>
            </div>

    </div>

</body>

</html>

后台Servlet代码

package Servlet;

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;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.Part;
import java.io.*;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;

@WebServlet(name = "ServletUpload",urlPatterns = {"/ServletUpload"})
public class ServletUpload extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        uploadFiles(request,response);
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        return;
    }

    private void uploadFiles(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        request.setCharacterEncoding("UTF-8");
        //String type=request.getParameter("type");

        try {
            // 配置上传参数
            DiskFileItemFactory factory = new DiskFileItemFactory();
            ServletFileUpload upload = new ServletFileUpload(factory);
            // 解析请求的内容提取文件数据
            @SuppressWarnings("unchecked")
            List<FileItem> formItems = upload.parseRequest(request);

            // 迭代表单数据
            for (FileItem item : formItems) {
                // 处理不在表单中的字段
                if (!item.isFormField()) {
                    String fileName = item.getName(); //获取上传的文件名
                    String fileType=fileName.substring(fileName.lastIndexOf(".")+1);
                    //定义上传文件的存放路径
                    String path = request.getServletContext().getRealPath("/upload");
                    //定义上传文件的完整路径
                    fileName= new SimpleDateFormat("yyyyMMddhhmmss").format(new Date()).toString();
                    fileName+="."+fileType;  //将文件名字改为时间，避免重名文件
                    String filePath = String.format("%s/%s",path,fileName);
                    File storeFile = new File(filePath);
                    // 在控制台输出文件的上传路径
                    System.out.println(path);
                    System.out.println(filePath);
                    // 保存文件到硬盘
                    item.write(storeFile);
                }
            }
        } catch (FileUploadException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }

//下面可以跳转到上传成功后的页面，这里演示就省略了
//        request.getRequestDispatcher("/success.jsp").forward(request, response);
    }

}