在网上查了很多，最后实现了。下面写一下过程：
首先,在WEBROOT/META-INF下建一个文件context.xml,内容为：
<?xml version="1.0" encoding="UTF-8"?> <Context> <Resource name="jdbc/ConnectionPool" auth="Application" type="javax.sql.DataSource" username="root" password="root" driverClassName="com.mysql.jdbc.Driver" url="jdbc:mysql://localhost:3306/sow" maxActive="8" maxIdle="4"/> </Context>
其中，name属性为数据库连接池的名称，auth属性为数据库连接池的作用范围，Application为作用于本web项目;url属性的后面sow为数据库名；
其次，在web.xml中添加配置：
<resource-ref> <description>news DataSource</description> <res-ref-name>jdbc/ConnectionPool</res-ref-name> <res-type>javax.sql.DataSource</res-type> <res-auth>Application</res-auth> </resource-ref>
注意里面的属性要一致。
接着，新建MyJsp.jsp用作测试
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <%@ page import="java.sql.*" %> <%@ page import="javax.naming.*" %> <%@ page import="javax.sql.DataSource" %> <% 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 'MyJsp.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> <% Context initCtx = new InitialContext(); Context ctx = (Context) initCtx.lookup("java:comp/env"); //获取连接池对象 DataSource ds =(DataSource)ctx.lookup("jdbc/ConnectionPool"); //创建连接 Connection conn = ds.getConnection(); System.out.println("conn="+conn); Statement stmt = conn.createStatement(); String mysql="select * from notification_tb"; ResultSet myrs=stmt.executeQuery(mysql); //执行查询 %> <body> This is my JSP page. <br> <table> <% while(myrs.next()) { %> <% String notiTheme=myrs.getString("notiTheme"); String notiContent=myrs.getString("notiContent"); %> <tr><td><%=notiTheme %></td><td><%=notiContent %></td></tr> <% System.out.println(notiTheme); System.out.println(notiContent); %> <% } %> </table> </body> </html>
然后重启TOMCAT,发布网站访问http://localhost:8080/PW_Application/MyJsp.jsp即可看到结果。