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来源: 作者: 时间:2016-01-25 09:47 【

0 IntroductionVersions of MySQL and JDBC drivers that have been reported to work:MySQL 3 23 47, MySQL 3 23 47 using InnoDB,, MySQL 3 23 58, MySQL 4 0 1alphaConnector

0. Introduction

Versions of MySQL and JDBC drivers that have been reported to work:

MySQL 3.23.47, MySQL 3.23.47 using InnoDB,, MySQL 3.23.58, MySQL 4.0.1alphaConnector/J 3.0.11-stable (the official JDBC Driver)mm.mysql 2.0.14 (an old 3rd party JDBC Driver)

Before you proceed, don't forget to copy the JDBC Driver's jar into $CATALINA_HOME/lib.

1. MySQL configuration

Ensure that you follow these instructions as variations can cause problems.

Create a new test user, a new database and a single test table. Your MySQL user must have a password assigned. The driver will fail if you try to connect with an empty password.

\ \ \
mysql> GRANT ALL PRIVILEGES ON *.* TO [email protected] 
mysql> create database javatest;
mysql> use javatest;
mysql> create table testdata (
    ->   id int not null auto_increment primary key,
    ->   foo varchar(25), 
    ->   bar int);
\ \ \
Note: the above user should be removed once testing is complete!

Next insert some test data into the testdata table.

\ \ \
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)

\ \ \

2. Context configuration

Configure the JNDI DataSource in Tomcat by adding a declaration for your resource to your Context.

For example:

\ \ \

    <!-- maxActive: Maximum number of database connections in pool. Make sure you
         configure your mysqld max_connections large enough to handle
         all of your db connections. Set to -1 for no limit.

    <!-- maxIdle: Maximum number of idle database connections to retain in pool.
         Set to -1 for no limit.  See also the DBCP documentation on this
         and the minEvictableIdleTimeMillis configuration parameter.

    <!-- maxWait: Maximum time to wait for a database 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.

    <!-- username and password: MySQL username and password for database connections  -->

    <!-- driverClassName: Class name for the old mm.mysql JDBC driver is - we recommend using Connector/J though.
         Class name for the official MySQL Connector/J driver is com.mysql.jdbc.Driver.
    <!-- url: The JDBC connection url for connecting to your MySQL database.

  <Resource name="jdbc/TestDB" auth="Container" type="javax.sql.DataSource"
               maxActive="100" maxIdle="30" maxWait="10000"
               username="javauser" password="javadude" driverClassName="com.mysql.jdbc.Driver"

\ \ \

3. web.xml configuration

Now create a WEB-INF/web.xml for this test application.

\ \ \
<web-app xmlns=""
  <description>MySQL Test App</description>
      <description>DB Connection</description>
\ \ \

4. Test code

Now create a simple test. page for use later.

\ \ \
<%@ taglib uri="" prefix="sql" %>
<%@ taglib uri="" prefix="c" %>

<sql:query var="rs" dataSource="jdbc/TestDB">
select id, foo, bar from testdata

    <title>DB Test</title>

<c:forEach var="row" items="${rs.rows}">
    Foo ${}<br/>
    Bar ${}<br/>

\ \ \

That JSP page makes use of JSTL's SQL and Core taglibs. You can get it from Apache Tomcat Taglibs - Standard Tag Library project — just make sure you get a 1.1.x release. Once you have JSTL, copy jstl.jar andstandard.jar to your web app's WEB-INF/lib directory.

Finally deploy your web app into $CATALINA_BASE/webapps either as a warfile called DBTest.war or into a sub-directory called DBTest

Once deployed, point a browser at http://localhost:8080/DBTest/test.jsp to view the fruits of your hard work.




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