想要实现servlet3.0的方式上传文件需要引入以来

<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.0.1</version>
<scope>provided</scope>
</dependency>

引入依赖后,开始编写,编写servlet文件
它会自动生成@WebServlet()
import javax.servlet.ServletException;
import javax.servlet.annotation.MultipartConfig;
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 javax.swing.*;
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Collection;
@WebServlet(name = "UploadServlet",urlPatterns="/UploadServlet")
@MultipartConfig
public class UploadServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("utf-8");
        //存储路径   “/upload文件夹需要你事先拥有,如idea中找到上传文件需要到target下的目录中”
        String savePath = request.getServletContext().getRealPath("/upload");
        //获取上传的文件集合
        Collection<Part> parts = request.getParts();
        //上传单个文件
        if (parts.size()==1) {
            Part part = request.getPart("file");
            String header = part.getHeader("content-disposition");
            System.out.println(header);
            //获取文件名
            String fileName = getFileName(header);
            System.out.println(fileName);
            //把文件写到指定路径
            part.write(savePath+ File.separator+fileName);
        }else {
            //一次性上传多个文件
            for (Part part : parts) {//循环处理上传的文件
                String header = part.getHeader("content-disposition");
                //获取文件名
                String fileName = getFileName(header);
                //把文件写到指定路径
                part.write(savePath+File.separator+fileName);
            }
        }
        PrintWriter out = response.getWriter();
        JOptionPane.showMessageDialog(null, "上传成功!");
        out.println("上传成功");
        out.flush();
        out.close();
    }
    
    public String getFileName(String header) {
        String[] tempArr1 = header.split(";");
        String[] tempArr2 = tempArr1[2].split("=");
        String fileName = tempArr2[1].substring(tempArr2[1].lastIndexOf("\\")+1).replaceAll("\"", "");
        return fileName;
    }

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

    其中urlPatterns 指的是你引用该servlet的名称,也就是action提交的路径

<%@page language="java" pageEncoding="UTF-8" isELIgnored="false" %>
<html>
<head>
    <title>Servlet3.0实现文件上传</title>
</head>
<body>
     上传单个文件
    <form action="/UploadServlet" method="post" enctype="multipart/form-data">
        上传文件:<input type="file" name="file"><br>
        <input type="submit" value="上传">
    </form>

<hr />
        上传多个文件
        <form action="/UploadServlet" method="post" enctype="multipart/form-data">
        上传文件:<input type="file" name="file1"><br>
        上传文件:<input type="file" name="file2"><br>
        <input type="submit" value="上传">
    </form>
</fieldset>
</body>
</html>

然后通过此方法即可上传成功。

posted on 2018-04-04 10:06  高尚的动物世界  阅读(153)  评论(0编辑  收藏  举报