1.导入jar包：commons-io-1.4.jar
2.index.jsp:
1 <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
2 <%
3 String path = request.getContextPath();
4 String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
5 %>
6
7 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
8 <html>
9 <head>
10 <base href="<%=basePath%>">
11
12 <title>文件上传</title>
13 <meta http-equiv="pragma" content="no-cache">
14 <meta http-equiv="cache-control" content="no-cache">
15 <meta http-equiv="expires" content="0">
16 <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
17 <meta http-equiv="description" content="This is my page">
18 <!--
19 <link rel="stylesheet" type="text/css" href="styles.css">
20 -->
21 </head>
22
23 <body>
24 <div><a href="${pageContext.request.contextPath}/showPic.jsp">查看图片</a></div>
25 </body>
26 </html>
3.showPic.jsp
1 <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
2 <%
3 String path = request.getContextPath();
4 String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
5 %>
6
7 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
8 <html>
9 <head>
10 <base href="<%=basePath%>">
11
12 <title>文件上传</title>
13 <meta http-equiv="pragma" content="no-cache">
14 <meta http-equiv="cache-control" content="no-cache">
15 <meta http-equiv="expires" content="0">
16 <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
17 <meta http-equiv="description" content="This is my page">
18 <!--
19 <link rel="stylesheet" type="text/css" href="styles.css">
20 -->
21 </head>
22
23 <body>
24 <div>
25 <img alt="图片" src="${pageContext.request.contextPath}/ShowPictureServlet?fileName=fanfan.jpg">
26 </div>
27 </body>
28 </html>
4.ShowPictureServlet.java
pacgake com.pearl.util;
1 import java.io.File;
2 import java.io.FileInputStream;
3 import java.io.IOException;
4 import java.io.OutputStream;
5
6 import javax.servlet.ServletConfig;
7 import javax.servlet.ServletException;
8 import javax.servlet.http.HttpServlet;
9 import javax.servlet.http.HttpServletRequest;
10 import javax.servlet.http.HttpServletResponse;
11
12 public class ShowPictureServlet extends HttpServlet {
13
14 public void destroy() {
15 super.destroy();
16 }
17
18 public void doGet(HttpServletRequest request, HttpServletResponse response)
19 throws ServletException, IOException {
20 //文件路径
21 String picFolder = "E:/upload/";
22 String fileName = request.getParameter("fileName");
23 if(fileName!=null && !fileName.equals("")){
24 String mimeType = "image/gif";
25 //设置content类型
26 response.setContentType(mimeType);
27 //设置大小
28 File file = new File(picFolder + fileName);
29 response.setContentLength((int) file.length());
30 //打开文件并输出
31 FileInputStream inputStream = new FileInputStream(file);
32 OutputStream out = response.getOutputStream();
33
34 //把文件复制到输出流
35 byte[] data = new byte[1024];
36 int count = 0;
37 while ((count=inputStream.read(data))>=0){
38 out.write(data, 0, count);
39 }
40 inputStream.close();
41 out.close();
42 }
43 }
44
45 public void doPost(HttpServletRequest request, HttpServletResponse response)
46 throws ServletException, IOException {
47 doGet(request, response);
48 }
49
50
51 public void init(ServletConfig config) throws ServletException {
52 super.init(config);
53 }
54
55 }
5.web.xml
1 <?xml version="1.0" encoding="UTF-8"?> 2 <web-app version="2.5" 3 xmlns="http://java.sun.com/xml/ns/javaee" 4 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 5 xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 6 http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> 7 <servlet> 8 <description>This is the description of my J2EE component</description> 9 <display-name>This is the display name of my J2EE component</display-name> 10 <servlet-name>ShowPictureServlet</servlet-name> 11 <servlet-class>com.pearl.util.ShowPictureServlet</servlet-class> 12 </servlet> 13 14 <servlet-mapping> 15 <servlet-name>ShowPictureServlet</servlet-name> 16 <url-pattern>/ShowPictureServlet</url-pattern> 17 </servlet-mapping> 18 19 <welcome-file-list> 20 <welcome-file>index.jsp</welcome-file> 21 </welcome-file-list> 22 </web-app>
6.完成。
时间： 2024-08-09 10:38:55