20160421javaweb之上传下载小案例---网盘

一、建立数据库：

CREATE TABLE IF NOT EXISTS `netdisk` (

  `id` int(10) NOT NULL AUTO_INCREMENT,

  `uuidname` varchar(255) NOT NULL,

  `realname` varchar(255) NOT NULL,

  `savepath` varchar(255) NOT NULL,

  `uploadtime` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,

  `description` varchar(255) NOT NULL,

  `ip` varchar(100) NOT NULL,

  PRIMARY KEY (`id`)

) ENGINE=InnoDB DEFAULT CHARSET=utf8;

二、功能分析：

index.jsp --- 提供上传下载列表
upload.jsp --- 提供上传表单,允许用户选择文件进行上传
UploadServlet --- 保存上传的文件到服务器/在数据库中保存文件相关的信息
DownListServlet --- 查询数据库表找到所有可供下载的资源信息,存入request域后带到页面显示
downlist.jsp --- 遍历request中所有资源信息,提供下载连接
DownServlet --- 下载指定id的资源

三、代码：

工程结构：

1.c3p0的配置文件，位于src目录

<c3p0-config>

  <default-config>

    <property name="driverClass">com.mysql.jdbc.Driver</property>

    <property name="jdbcUrl">jdbc:mysql://localhost:3306/0417?Unicode=true&amp;characterEncoding=utf-8</property>

    <property name="user">root</property>

    <property name="password"></property>

  </default-config>

</c3p0-config>

c3p0-config.xml

2.javabean 类位于domain包

package com.dzq.domain;

import java.io.Serializable;

import java.sql.Timestamp;

public class Resource implements Serializable {

    private int id;

    private String uuidname; // 上传文件的名称，文件的uuid名

    private String realname; // 上传文件的真实名称

    private String savepath; // 记住文件的位置

    private Timestamp uploadtime; // 文件的上传时间

    private String description; // 文件的描述

    private String ip;

    public int getId() {

        return id;

    }

    public void setId(int id) {

        this.id = id;

    }

    public String getUuidname() {

        return uuidname;

    }

    public void setUuidname(String uuidname) {

        this.uuidname = uuidname;

    }

    public String getRealname() {

        return realname;

    }

    public void setRealname(String realname) {

        this.realname = realname;

    }

    public String getSavepath() {

        return savepath;

    }

    public void setSavepath(String savepath) {

        this.savepath = savepath;

    }

    public Timestamp getUploadtime() {

        return uploadtime;

    }

    public void setUploadtime(Timestamp uploadtime) {

        this.uploadtime = uploadtime;

    }

    public String getDescription() {

        return description;

    }

    public void setDescription(String description) {

        this.description = description;

    }

    public String getIp() {

        return ip;

    }

    public void setIp(String ip) {

        this.ip = ip;

    }

}

Resource.java

3.工具类位于utils包

package com.dzq.utils;

import java.sql.Connection;

import java.sql.SQLException;

import javax.sql.DataSource;

import com.mchange.v2.c3p0.ComboPooledDataSource;

public class DaoUtils {

    private static DataSource source = new ComboPooledDataSource();

    private DaoUtils() {

    }

    public static DataSource getSource() {

        return source;

    }

    public static Connection getConnection() {

        try {

            return source.getConnection();

        } catch (SQLException e) {

            e.printStackTrace();

            throw new RuntimeException(e);

        }

    }

}

DaoUtils.java

package com.dzq.utils;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

public class IOUtils {

   private IOUtils(){

   }

   public static void In2Out(InputStream in,OutputStream out) throws IOException{

       byte[] bs=new byte[1024];

       int i=0;

       while ((i=in.read(bs))!=-1) {

        out.write(bs,0,i);

    }

   }

   public static void close(InputStream in,OutputStream out){

       if(in!=null){

           try {

            in.close();

        } catch (IOException e) {

            e.printStackTrace();

        }finally{

            in=null;

        }

       }

       if(out!=null){

           try {

            out.close();

        } catch (IOException e) {

            e.printStackTrace();

        }finally{

            out=null;

        }

       }

   }

}

IOUtils.java

4.servlet位于web包

package com.dzq.web;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

import java.util.UUID;

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 org.apache.commons.beanutils.BeanUtils;

import org.apache.commons.dbutils.QueryRunner;

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 com.dzq.domain.Resource;

import com.dzq.utils.DaoUtils;

import com.dzq.utils.IOUtils;

@WebServlet("/UploadServlet")

public class UploadServlet extends HttpServlet {

    private static final long serialVersionUID = 1L;

    protected void doGet(HttpServletRequest request,

            HttpServletResponse response) throws ServletException, IOException {

        try {

            // 1.上传文件

            // 设置文件上传的路径和临时路径

            String upload = this.getServletContext().getRealPath(

                    "/WEB-INF/upload");

            String temp = this.getServletContext().getRealPath("/WEB-INF/temp");

            Map pmap = new HashMap();

            pmap.put("ip", request.getRemoteAddr());

            // 创建工厂

            DiskFileItemFactory factory = new DiskFileItemFactory();

            // 设置内存

            factory.setSizeThreshold(1024 * 100);

            // 设置临时目录

            factory.setRepository(new File(temp));

            ServletFileUpload fileupload = new ServletFileUpload(factory);

            // 防止文件中文名乱码

            fileupload.setHeaderEncoding("utf-8");

            // 设置单个文件最大值

            fileupload.setFileSizeMax(1024 * 1024 * 100);

            // 设置总文件最大值

            fileupload.setSizeMax(1024 * 1024 * 200);

            // 检查表单是否正确

            if (!fileupload.isMultipartContent(request)) {

                throw new RuntimeException("表单不正确");

            }

            List<FileItem> list = fileupload.parseRequest(request);

            for (FileItem item : list) {

                if (item.isFormField()) {

                    String name = item.getFieldName();

                    String value = item.getString("utf-8");

                    pmap.put(name, value);

                } else {

                    // 获取文件名

                    String realname = item.getName();

                    // 设置文件的UUID文件名，防止文件名重复

                    String uuidname = UUID.randomUUID().toString() + "_"

                            + realname;

                    // 计算uuid哈希值

                    String hash = Integer.toHexString(uuidname.hashCode());

                    String savepath = "/WEB-INF/upload";

                    pmap.put("realname", realname);

                    pmap.put("uuidname", uuidname);

                    InputStream in = item.getInputStream();

                    for (char c : hash.toCharArray()) {

                        // 根据哈希值分布存储

                        upload += "/" + c;

                        savepath += "/" + c;

                    }

                    new File(upload).mkdirs();

                    pmap.put("savepath", savepath);

                    OutputStream out = new FileOutputStream(new File(upload,

                            uuidname));

                    IOUtils.In2Out(in, out);

                    IOUtils.close(in, out);

                    // 删除临时文件

                    item.delete();

                }

            }

            // 2.向数据库写入数据

            Resource r = new Resource();

            BeanUtils.populate(r, pmap);

            QueryRunner runner = new QueryRunner(DaoUtils.getSource());

            String sql = "insert into netdisk values (null,?,?,?,null,?,?)";

            runner.update(sql, r.getUuidname(), r.getRealname(),

                    r.getSavepath(), r.getDescription(), r.getIp());

            // 3.重定向回主页

            response.sendRedirect(request.getContextPath() + "/index.jsp");

        } catch (Exception e) {

            e.printStackTrace();

            throw new RuntimeException(e);

        }

    }

    protected void doPost(HttpServletRequest request,

            HttpServletResponse response) throws ServletException, IOException {

        doGet(request, response);

    }

}

UploadServlet.java

package com.dzq.web;

import java.io.IOException;

import java.sql.SQLException;

import java.util.List;

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 org.apache.commons.dbutils.QueryRunner;

import org.apache.commons.dbutils.handlers.BeanListHandler;

import com.dzq.domain.Resource;

import com.dzq.utils.DaoUtils;

@WebServlet("/DownListServlet")

public class DownListServlet extends HttpServlet {

    private static final long serialVersionUID = 1L;

    protected void doGet(HttpServletRequest request,

            HttpServletResponse response) throws ServletException, IOException {

        // 1.查找数据库中所有可供下载的资源

        String sql = "select * from netdisk ";

        QueryRunner runner = new QueryRunner(DaoUtils.getSource());

        List<Resource> list = null;

        try {

            list = runner.query(sql, new BeanListHandler<Resource>(

                    Resource.class));

        } catch (SQLException e) {

            e.printStackTrace();

            throw new RuntimeException(e);

        }

        // 2.存入request域

        request.setAttribute("list", list);

        request.getRequestDispatcher("/downlist.jsp")

                .forward(request, response);

    }

    protected void doPost(HttpServletRequest request,

            HttpServletResponse response) throws ServletException, IOException {

        doGet(request, response);

    }

}

DownListServlet.java

package com.dzq.web;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.net.URLEncoder;

import java.sql.SQLException;

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 org.apache.commons.dbutils.QueryRunner;

import org.apache.commons.dbutils.handlers.BeanHandler;

import com.dzq.domain.Resource;

import com.dzq.utils.DaoUtils;

import com.dzq.utils.IOUtils;

@WebServlet("/DownServlet")

public class DownServlet extends HttpServlet {

    private static final long serialVersionUID = 1L;

    protected void doGet(HttpServletRequest request,

            HttpServletResponse response) throws ServletException, IOException {

        String id = request.getParameter("id");

        String sql = "select * from netdisk where id=?";

        QueryRunner runner = new QueryRunner(DaoUtils.getSource());

        Resource r = null;

        try {

            r = runner

                    .query(sql, new BeanHandler<Resource>(Resource.class), id);

        } catch (SQLException e) {

            e.printStackTrace();

        }

        if (r == null) {

            response.getWriter().write("对不起，资源不存在了");

            return;

        } else {

            response.setHeader("Content-Disposition", "attachment;filename="

                    + URLEncoder.encode(r.getRealname(), "utf-8"));

            response.setContentType(this.getServletContext().getMimeType(

                    r.getRealname()));// MIME类型

            String filepath = this.getServletContext().getRealPath(

                    r.getSavepath() + "/" + r.getUuidname());

            InputStream in = new FileInputStream(new File(filepath));

            OutputStream out = response.getOutputStream();

            IOUtils.In2Out(in, out);

            IOUtils.close(in, out);

            IOUtils.close(in, null);

        }

    }

    protected void doPost(HttpServletRequest request,

            HttpServletResponse response) throws ServletException, IOException {

        doGet(request, response);

    }

}

DownServlet.java

5.jsp页面，位于WebContent目录下

<%@ page language="java" contentType="text/html; charset=UTF-8"

    pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<title>Insert title here</title>

</head>

<body>

<h1>小强网盘</h1><hr>

<a href="${pageContext.request.contextPath }/upload.jsp">上传</a>

<a href="${pageContext.request.contextPath }/DownListServlet">下载列表</a>

</body>

</html>

index.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"

    pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<title>Insert title here</title>

</head>

<body>

<h1>上传页面</h1><hr>

<form action="${pageContext.request.contextPath }/UploadServlet" method="post" enctype="multipart/form-data">

选择文件：<input type="file" name="file1"/><br>

描述信息：<textarea rows="5" cols="45" name="description"></textarea><br>

<input type="submit" value="上传"/>

</form>

</body>

</html>

upload.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"

    pageEncoding="UTF-8"%>

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<title>Insert title here</title>

</head>

<body>

<h1>下载列表</h1><hr>

<c:forEach items="${requestScope.list }" var="r">

   <h2>文件名：${r.realname }</h2><br>

    上传时间：${r.uploadtime }<br>

    上传者IP：${r.ip }<br>

    描述信息：${r.description }<br>

 <a href="${pageContext.request.contextPath }/DownServlet?id=${r.id}">下载</a>

 <hr>

</c:forEach>

</body>

</html>

downlist.jsp

运行截图：

下载地址：

使劲点我呀

巴特西

20160421javaweb之上传下载小案例---网盘

最新文章

热门文章