一、前言
其实,改写后的JDBC Data-Source是运行在Servlet中的,通过JNDI去查找数据源。我用Orion试的,将本站《JAVA/JSP学习系列之六(MySQL翻页例子) 》 简单改写了一下。
二、配置
(1)JDBC
需要将用到的JDBC驱动Copy到[ORION]/lib目录下
(2)data-source
在[ORION]/config/data-sources.xml文件中加入如下:
〈data-source
class="com.evermind.sql.DriverManagerDataSource"
name="mySqlDbpage"
location="jdbc/HypersonicCoreDS"
xa-location="jdbc/xa/HypersonicXADS"
ejb-location="jdbc/mysqlDbPage"
connection-driver="org.gjt.mm.mysql.Driver"
username="root"
password=""
url="jdbc:mysql://localhost/test"
inactivity-timeout="30"
/〉
需要注意的是:
(1)ejb-location这个后面的“jdbc/mysqlDbPage”是JNDI要来查找的。
(2)connection-driver为JDBC数据库驱动
(3)url是JDBC中的URL
(4)username为数据库用户名
(5)password为用户密码
(6)inactivity-timeout为数据库连接超时,默认为30秒
对于其他的地方不要改。
三、改写后的代码如下:
//建立一个JNDI查找对象
InitialContext JNDI_Context = new InitialContext();
//JNDI查找数据源
DataSource ds = (DataSource) JNDI_Context.lookup("jdbc/mysqlDbPage");
//得到一个数据源连接
Connection conn = ds.getConnection();
int intPageSize; //一页显示的记录数
int intRowCount; //记录总数
int intPageCount; //总页数
int intPage; //待显示页码
java.lang.String strPage;
int i;
//设置一页显示的记录数
intPageSize = 2;
//取得待显示页码
strPage = request.getParameter("page");
if(strPage==null){
//表明在QueryString中没有page这一个参数,此时显示第一页数据
intPage = 1;
} else{
//将字符串转换成整型
intPage = java.lang.Integer.parseInt(strPage);
if(intPage
}
// 得到结果
stmt = conn.createStatement();
ResultSet sqlRst = stmt.executeQuery("select f1 from test");
//获取记录总数
sqlRst.last();
intRowCount = sqlRst.getRow();
//记算总页数
intPageCount = (intRowCount+intPageSize-1) / intPageSize;
//调整待显示的页码
if(intPage>intPageCount)
intPage = intPageCount;
%>

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