简介
下面这些的MySQL和JDBC驱动的版本可以运作：
- MySQL 3.23.47, MySQL 3.23.47 using InnoDB,, MySQL 3.23.58, MySQL 4.0.1alpha
- Connector/J 3.0.11-stable (the official JDBC Driver)
- mm.mysql 2.0.14 (an old 3rd party JDBC Driver)
在你开始之前，别忘记复制一份JDBC驱动的jar文件到$CATALINA_HOME/common/lib里面。
MySQL 配置
你一定要遵循这些指导说明，因为变动会产生问题。
产生一个新的测试用户，一个新的数据库和一个测试表格。你的MySQL用户必须要有个指派的密码。如果你试图用空密码连接，驱动会失败。
 | | |
| mysql> GRANT ALL PRIVILEGES ON *.* TO javauser@localhost
-> IDENTIFIED BY 'javadude' WITH GRANT OPTION;
mysql> create database javatest;
mysql> use javatest;
mysql> create table testdata (
-> id int not null auto_increment primary key,
-> foo varchar(25),
-> bar int); | |
| | |
注意：当测试完成以后，上面的用户应该被删除掉。
下一步，在testdata表格中加入一些测试数据。
| | |
| mysql> insert into testdata values(null, 'hello', 12345);
Query OK, 1 row affected (0.00 sec)
mysql> select * from testdata;
+----+-------+-------+
| ID | FOO | BAR |
+----+-------+-------+
| 1 | hello | 12345 |
+----+-------+-------+
1 row in set (0.00 sec)
mysql> | |
| | |
server.xml 配置
通过向$CATALINA_HOME/conf/server.xml里面加入一个声明来在Tomcat里配置JNDI DataSource。
在例子的</Context>标志与关闭局部主机的</Host>标志之间添加它。
| | |
| <Context path="/DBTest" docBase="DBTest"
debug="5" reloadable="true" crossContext="true">
<Logger className="org.apache.catalina.logger.FileLogger"
prefix="localhost_DBTest_log." suffix=".txt"
timestamp="true"/>
<Resource name="jdbc/TestDB"
auth="Container"
type="javax.sql.DataSource"/>
<ResourceParams name="jdbc/TestDB">
<parameter>
<name>factory</name>
<value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
</parameter>
<!-- Maximum number of dB connections in pool. Make sure you
configure your mysqld max_connections large enough to handle
all of your db connections. Set to 0 for no limit.
-->
<parameter>
<name>maxActive</name>
<value>100</value>
</parameter>
<!-- Maximum number of idle dB connections to retain in pool.
Set to -1 for no limit. See also the DBCP documentation on this
and the minEvictableIdleTimeMillis configuration parameter.
-->
<parameter>
<name>maxIdle</name>
<value>30</value>
</parameter>
<!-- Maximum time to wait for a dB connection to become available
in ms, in this example 10 seconds. An Exception is thrown if
this timeout is exceeded. Set to -1 to wait indefinitely.
-->
<parameter>
<name>maxWait</name>
<value>10000</value>
</parameter>
<!-- MySQL dB username and password for dB connections -->
<parameter>
<name>username</name>
<value>javauser</value>
</parameter>
<parameter>
<name>password</name>
<value>javadude</value>
</parameter>
<!-- Class name for the old mm.mysql JDBC driver - uncomment this entry and comment next
if you want to use this driver - we recommend using Connector/J though
<parameter>
<name>driverClassName</name>
<value>org.gjt.mm.mysql.Driver</value>
</parameter>
-->
<!-- Class name for the official MySQL Connector/J driver -->
<parameter>
<name>driverClassName</name>
<value>com.mysql.jdbc.Driver</value>
</parameter>
<!-- The JDBC connection url for connecting to your MySQL dB.
The autoReconnect=true argument to the url makes sure that the
mm.mysql JDBC Driver will automatically reconnect if mysqld closed the
connection. mysqld by default closes idle connections after 8 hours.
-->
<parameter>
<name>url</name>
<value>jdbc:mysql://localhost:3306/javatest?autoReconnect=true</value>
</parameter>
</ResourceParams>
</Context> | |
| | |
web.xml 配置
现在为这个测试程序产生一个WEB-INF/web.xml 文件。
| | |
| <web-app xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"
version="2.4">
<web-app>
<description>MySQL Test App</description>
<resource-ref>
<description>DB Connection</description>
<res-ref-name>jdbc/TestDB</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
</web-app> | |
| | |
测试代码
现在产生一个简单的test.jsp页面供以后使用。
| | |
| <%@ taglib uri="http://java.sun.com/jsp/jstl/sql" prefix="sql" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<sql:query var="rs" dataSource="jdbc/TestDB">
select id, foo, bar from testdata
</sql:query>
<html>
<head>
<title>DB Test</title>
</head>
<body>
<h2>Results</h2>
<c:forEach var="row" items="${rs.rows}">
Foo ${row.foo}<br/>
Bar ${row.bar}<br/>
</c:forEach>
</body>
</html> | |
| | |
JSP页面利用JSTL 's SQL 和 Core taglibs 。你可以从Sun's Java Web Services Developer Pack 得到它，或者从Jakarta Taglib Standard 1.1 project 得到它——确保你拿到的是1.1.x发行版。当你有了JSTL以后，把jstl.jar和standard.jar复制到你的网络程序的WEB-INF/lib目录里。
最后把你的网络程序作为DBTest.warDBTest的子目录形式部署到$CATALINA_HOME/webapps 里面。
当部署完成后，在一个浏览器里指向http://localhost:8080/DBTest/test.jsp就可以看到你辛勤劳动的成果了。
