javabean使用连接池有关问题,SOS,ing

javabean使用连接池问题,SOS,在线等ing
连接池配置好了,且在jsp中测试也通过了,代码:
<%@   page   contentType= "text/html;charset=gb2312 "%>
<%@   page   import= "javax.naming.Context "   %>
<%@   page   import= "javax.sql.DataSource "   %>
<%@   page   import= "javax.naming.InitialContext "   %>
<%@   page   import= "java.sql.* "   %>

<%
DataSource   ds   =   null;
try
{
Context   initCtx   =   new   InitialContext();
out.println(1);
Context   envCtx   =   (Context)initCtx.lookup( "java:comp/env ");
out.println(2);
ds   =   (DataSource)envCtx.lookup( "jdbc/Jsp_BBS ");
out.println(3);
if   (ds   !=   null)
{
out.println( "已经获得DataSource! ");
out.println( " <br> ");
Connection   conn   =   ds.getConnection();
Statement   stmt   =   conn.createStatement();
out.println( "success! ");
}
}
catch(Exception   e)
{
out.println(e.getMessage());
}
%>

但在javabean中使用却出错了,提示的错误:
Need   to   specify   class   name   in   environment   or   system   property,   or   as   an   applet   parameter,   or   in   an   application   resource   file:     java.naming.factory.initial

代码是:
package   com.bean;

import   java.sql.*;

import   javax.naming.*;
import   javax.sql.*;

public   class   dbControl  
{
DataSource   ds   =   null;
Connection   conn;
String   strSql;
final   static   String   datasource   =   "java:comp/env/jdbc/Jsp_BBS ";

public   dbControl()
{
try
{
Context   initCtx   =   new   InitialContext();
                        //lookup(String   name)：返回与指定的名字绑定的对象,获得数据库连接工厂
                        ds   =   (DataSource)initCtx.lookup( "java:comp/env/jdbc/Jsp_BBS ");
//Context   initCtx   =   new   InitialContext();
//Context   envCtx   =   (Context)initCtx.lookup( "java:comp/env ");
//ds   =   (DataSource)initCtx.lookup(datasource);
conn   =   ds.getConnection();
}
catch(Exception   e)
{
System.out.println(e.getMessage());
}
}

public   dbControl(String   strSql)
{
this();
this.strSql   =   strSql;  
}
public   static   void   main(String   []   args)
{
dbControl   db   =   new   dbControl();
}
}


------解决方案--------------------
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