简单 文件上传
index.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>文件上传页面测试</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<form action="servlet/UpLoad" method="post" enctype="multipart/form-data">
<input type="file" name="uploadfile">
<input type="submit" name="submit" value="上传">
</form>
</body>
</html>
showpic.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ page import="java.sql.*,javax.sql.*,javax.naming.*,java.io.*"%>
<!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>显示数据库中的图片对象</title>
</head>
<body>
上传用户名:${requestScope.username }<br>
<img src="ShowImage?picid=23" width="500px" height="600px">
<!-- 读取查询数据库中的图片对象 -->
<%--
Context context=new InitialContext();
DataSource ds=(DataSource)context.lookup("java:/comp/env/jdbc/upload");
Connection con=ds.getConnection();
String sql="select pic_image from pic where pic_id=23";
PreparedStatement preparedStatement= con.prepareStatement(sql);
ResultSet rs=preparedStatement.executeQuery(); //得到查询结果集
Blob picture=null;
if(rs.next()){
picture=rs.getBlob(1);
long size=picture.length(); //得到图片长度
byte [] bs=picture.getBytes(1,(int)size);
OutputStream os=response.getOutputStream();
os.write(bs); //指定byte数组写入输出流
os.flush(); //刷新输出流,写出缓冲的输出字节
out.clear(); //JspWriter
out = pageContext.pushBody(); //BodyContent is a subclass of JspWriter 返回一个空的out对象
//public BodyContent pushBody()
//Return a new BodyContent object, save the current "out" JspWriter,
//and update the value of the "out" attribute in the page scope attribute namespace of the PageContext
//public abstract void clear()throws IOException
//Clear the contents of the buffer.
//If the buffer has been already been flushed
//then the clear operation shall throw an IOException to signal the fact that
//some data has already been irrevocably written to the client response stream
}else{
out.println("没有找到图片");
}
--%>
</body>
</html>
uploadDatabase.jsp
<%@ page language="java" pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>文件上传例题</title>
<style type="text/css">
form{ margin-top:100px;}
</style>
</head>
<body>
目录1:<%=request.getSession().getServletContext().getContextPath()%>
目录2:<%=request.getSession().getServletContext().getRealPath("/")%>
<form action="servlet/UpLoadDatabase" method="post" enctype="multipart/form-data" name="form1" id="form1">
<table width="580" border="0" align="center" cellpadding="10" cellspacing="1" bgcolor="#999999">
<tr>
<td bgcolor="#FFFFFF">网名:</td>
<td colspan="2" bgcolor="#FFFFFF"><input name="username" type="text" id="username" /></td>
</tr>
<tr>
<td bgcolor="#FFFFFF">文件:</td>
<td colspan="2" bgcolor="#FFFFFF"><input type="file" name="file" /></td>
</tr>
<tr>
<td bgcolor="#FFFFFF"> </td>
<td bgcolor="#FFFFFF"><input name="submit" type="submit" id="submit" value="提交" /></td>
<td bgcolor="#FFFFFF"><input name="reset" type="reset" id="reset" value="刷新" /></td>
</tr>
</table>
</form>
</body>
</html>
package servlets;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.InputStream;
import java.sql.*;
import javax.naming.*;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.sql.*;
import javax.imageio.*;
public class ShowImage extends HttpServlet {
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
System.out.println("图片查un:"+request.getParameter("picid"));
//从客户端获取要查询的ID
Integer picid=new Integer(request.getParameter("picid"));
System.out.println("图片的ID"+picid);
//数据库连接对象,方便finally使用
Connection con=null;
//预处理命令对象
PreparedStatement ps=null;
//结果集对象
ResultSet rs=null;
try{
Context context=new InitialContext();
DataSource ds=(DataSource)context.lookup("java:comp/env/jdbc/upload");
//得到数据库连接对象
con=ds.getConnection();
String sql="select pic_image from pic where pic_id=?";
ps=con.prepareStatement(sql);
//设置查询参数
ps.setInt(1,picid);
//执行查询
rs=ps.executeQuery();
if(rs.next()){
response.setContentType("image/png");
Blob pic=rs.getBlob(1);
System.out.println(pic);
//得到向客户端响应的输出流
ServletOutputStream sos=response.getOutputStream();
//通过二进制大对象得到输入流
InputStream is=pic.getBinaryStream();
//通过ImageIO的静态方法得到BufferedImage
BufferedImage image=ImageIO.read(is);
System.out.println("图片"+pic);
/*
* 使用指定的png格式把(实现RenderedImage接口的BufferedImage)
* image对象写入OutputStream 类型对象
*/
ImageIO.write(image,"png",sos);
//关闭输入流对象
is.close();
//刷新输出流,写出缓冲的输出字节
sos.flush();
sos.close();
}
}catch(Exception e){
e.printStackTrace();
}finally{
try {
if(con!=null){
con.close();
}
} catch (SQLException e) {
e.printStackTrace();
}//关闭数据库连接try块
}
}
public void init() throws ServletException {
}
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request,response);
}
}
package servlets;
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.*;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.fileupload.*;
public class UpLoad extends HttpServlet {
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
try{
DiskFileUpload fu=new DiskFileUpload();
PrintWriter out=response.getWriter();
//设置上传对象的字符编码和request一致
fu.setHeaderEncoding(request.getCharacterEncoding());
//限制上传文件大小
fu.setSizeMax(1024*1024*16);
//设置临时保存解析占用内存空间大小
fu.setSizeThreshold(1024*1024*16);
List fileItems=fu.parseRequest(request);
Iterator it=fileItems.iterator();
FileItem fi=(FileItem)it.next(); //解析成fileItem
String name=fi.getName(); //得到文件路径和名字
if(name.lastIndexOf("\\")!=-1){
//得到文件名去除路径名
String filename=name.substring(name.lastIndexOf("\\"));
String webdir=request.getSession().getServletContext().getRealPath("/");
fi.write(new File(webdir+"uploadimage"+filename));
out.print("上传成功");
}else{
out.print("上传失败!");
}
}catch(Exception e){
e.printStackTrace();
}
}
public void init() throws ServletException {
}
}
/**
* 上传信息到数据库包括图片
*/
package servlets;
import java.io.*;
import java.util.*;
import java.sql.*;
import javax.naming.*;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.sql.*;
import org.apache.commons.fileupload.*;
/**
*
*
*/
public class UpLoadDatabase extends HttpServlet {
private static final long serialVersionUID = 5220553409822159109L;
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request,response);
}
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
DiskFileUpload df=new DiskFileUpload();
df.setHeaderEncoding(request.getCharacterEncoding());
df.setSizeMax(1024*1024*16); //设置文件最大为16M
df.setSizeThreshold(1024*1024*3); //设置内存中缓冲3M
if(df.isMultipartContent(request)){
InputStream is=null;
PreparedStatement pst=null;
Connection con=null;
try {
Map map=new HashMap();
List fileList=df.parseRequest(request); //解析请求到list集合
Iterator fileItems=fileList.iterator(); //迭代器
while(fileItems.hasNext()){
FileItem ft=(FileItem)fileItems.next();
if(ft.isFormField()){ //如果不是文件
map.put(ft.getFieldName(),ft.getString());
request.setAttribute(ft.getFieldName(),ft.getString());
}else{
map.put(ft.getFieldName(),ft);
}
}//遍历迭代器对象循环
FileItem file=(FileItem)map.get("file");
Context context = new InitialContext();
DataSource ds = (DataSource) context.lookup("java:comp/env/jdbc/upload");
con = ds.getConnection();
String inserta = "insert into pic (pic_name,pic_image) values (?,?)";
pst = con.prepareStatement(inserta);
pst.setString(1, map.get("username").toString());
is = file.getInputStream(); //得到文件输入流
pst.setBinaryStream(2, is, (int)file.getSize());
int result = pst.executeUpdate(); //执行更新插入数据
if (result >= 1) {
request.setAttribute("result", "上传文件成功!");
} else {
request.setAttribute("result", "上传文件失败!");
}//判断是否上传成功块结束
} catch (Exception e) {
System.out.println(new String(e.getMessage().getBytes("ISO-8859-1"),"GBK"));
e.printStackTrace();
}finally{
try {
pst.close();
con.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}else{
request.setAttribute("result","只能处理multipart/form-data类型的数据!");
return;
}//判断是否是multipart/form-data类型数据块结束
//request.setAttribute("picid",23);
System.out.println("目录1"+request.getSession().getServletContext().getContextPath());
System.out.println("目录2"+request.getSession().getServletContext().getRealPath("/"));
RequestDispatcher td=request.getRequestDispatcher("../showpic.jsp?picid=23");
td.forward(request,response);
}
}
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