Servlet 文件上传-白红宇

Servlet 文件上传

阅读量：5235 次

发布时间：2019-06-14

本文共 2141 字，大约阅读时间需要 7 分钟。

pom.xml 中先添加依赖


        
     
      javax.servlet
         
     
      javax.servlet-api
         
     
      3.1.0
         
     
      provided

上传用的 JSP

<%@ page contentType="text/html" pageEncoding="UTF-8" language="java" %>    File Upload    Select a file:

创建 Servlet 类

package com.seliote;import javax.servlet.ServletException;import javax.servlet.http.Part;import java.io.ByteArrayOutputStream;import java.io.IOException;import java.io.InputStream;public class FileUploadServlet extends javax.servlet.http.HttpServlet {    protected void doPost(javax.servlet.http.HttpServletRequest request,                          javax.servlet.http.HttpServletResponse response)            throws ServletException, IOException {        // Get Part        Part part = request.getPart("userFile");        if (part == null) {            // Log it            return;        }        // Read file        InputStream inputStream = part.getInputStream();        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();        byte[] buffer = new byte[1024];        int readLength = -1;        while ((readLength = inputStream.read(buffer)) != -1) {            byteArrayOutputStream.write(buffer, 0, readLength);        }        response.getWriter().println("file length: " + byteArrayOutputStream.size());        byteArrayOutputStream.close();    }    protected void doGet(javax.servlet.http.HttpServletRequest request,                         javax.servlet.http.HttpServletResponse response)            throws ServletException, IOException {        request.getRequestDispatcher("/index.jsp").forward(request, response);    }}

修改部署描述符 web.xml


        
     
      FileUploadServlet
         
     
      com.seliote.FileUploadServlet
         
         
             
              
      
       /tmp
              
              
      
       20971520
              
              
      
       41943040
              
              
      
       5242880
          
     
    
        
     
      FileUploadServlet
         
     
      /upload