📄 jsp1.txt
字号:
1.处理读取图片请求的servlet
public class ReadeImgServlet extends HttpServlet {
public void doGet(HttpServletRequest req, HttpServletResponse res)
throws ServletException, java.io.IOException {
res.setContentType("Image/jpg");
OutputStream out = res.getOutputStream();//获得响应的输出流，并将数据写入到客户端
Connection con = null;
Statement stmt = null;
ResultSet rs = null;
String drivername = "com.mysql.jdbc.Driver";
String url = "jdbc:mysql://localhost:3306/mysql?user=root&password=871224";
String sql = "select * from imgtab ";
try {
Class.forName(drivername);
con = DriverManager.getConnection(url);
stmt = con.createStatement();
rs = stmt.executeQuery(sql);
if (rs.next()) {
java.io.InputStream in = rs.getBinaryStream(1);//此流是远程流长度是不可测的
byte b[] = new byte[in.available()];
while (true) {
int readLength = in.read(b);
if (readLength == -1) {
break;
}
out.write(b, 0, b.length);//实现将数据写到客户端的jsp页面中
}
}
} catch (Exception ex) {
ex.printStackTrace();
} finally {
try {
if (stmt != null) {
stmt.close();
}
if (con != null) {
con.close();
}
} catch (Exception ex) {
ex.printStackTrace();
}
}
}
}
2.web.xml配置：
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>readeImg</servlet-name>
<servlet-class>com.tarena.dao.entity.ReadeImgServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>readeImg</servlet-name>
<url-pattern>/readeImg.do</url-pattern>
</servlet-mapping>
</web-app>
3.jsp页面中的<img>:
<%@ page language="java" import="java.util.*" pageEncoding="ISO-8859-1" isELIgnored="false"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'index.jsp' starting page</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>
This is my JSP page. <img border="0" src="<%=basePath%>readeImg.do"/>
</body>
</html>⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -