第一次配置TOMCAT的连接池,快绝望了,救命啊~
Cannot   create   JDBC   driver   of   class    ' '   for   connect   URL    'null '      
 .jar已经放到\Tomcat\common\lib下和web目录的WEB-INF\lib
------解决方案--------------------http://shanmin2005.bokee.com/viewdiary.14505702.html
------解决方案--------------------sunwei_07 ()一个问题你要问80遍 别人一说就明白您老呀 还是转行吧 
 在%TOMCAT_HOME%/conf/Catalina/localhost下新建一个与你web文件夹同名的xml文件 
  <?xml version= "1.0 " encoding= "UTF-8 "?>  
  <Context>  
       <Resource 
       name= "jdbc/****** " 
       type= "javax.sql.DataSource " 
       password= "123456 " 
       driverClassName= "com.microsoft.jdbc.sqlserver.SQLServerDriver " 
       maxIdle= "2 " 
       maxWait= "5000 " 
       username= "sa " 
       url= "jdbc:microsoft:sqlserver://localhost;DatabaseName=quickstart " 
       maxActive= "4 "/>   
  </Context> 根据个人具体情况进行相应修改。 
 TOMCAT把work\Catalina下localhost删掉 然后在重起TOMCAT
------解决方案--------------------看看这个 http://www.haolla.com/girls/index.asp 
          http://haolla.com/wy
------解决方案--------------------把你LIB包里面JTDS包DEL掉 
 还不行到MSN告诉我 我就不信教不会你了
------解决方案--------------------Tomcat 5.0.28配置如下: 
 ================================ 
  <Context crossContext= "true " displayName= "Test " docBase= "Test " path= "/Test " workDir= "work\Catalina\localhost\Test ">  
    <Resource auth= "Container " name= "jdbc/Data " type= "javax.sql.DataSource "/>  
    <ResourceParams name= "jdbc/Data ">  
      <parameter>  
        <name> factory </name>  
        <value> org.apache.commons.dbcp.BasicDataSourceFactory </value>  
      </parameter>  
      <parameter>  
        <name> url </name>  
        <value> jdbc:mysql://192.168.1.100/test?useUnicode=true </value>  
      </parameter>  
 	 <parameter>  
        <name> username </name>  
        <value> root </value>  
      </parameter>  
      <parameter>  
        <name> password </name>  
        <value>  
 	   </value>  
      </parameter>  
      <parameter>  
        <name> maxWait </name>  
        <value> 1 </value>  
      </parameter>  
      <parameter>  
        <name> maxActive </name>  
        <value> 5 </value>  
      </parameter>  
      <parameter>  
        <name> driverClassName </name>  
        <value> org.gjt.mm.mysql.Driver </value>  
      </parameter>        
      <parameter>  
        <name> maxIdle </name>  
        <value> 1 </value>  
      </parameter>  
    </ResourceParams>  
  </Context>  
 访问如下: 
 ------------------------------- 
  <%@page contentType= "text/html;charset=gb2312 " import= "javax.sql.*,javax.naming.*,java.sql.*,dev.sql.DataSource "%>  
  <% 
 		Connection con=null; 
 		DataSource t=null; 
 		try{ 
 			t=new DataSource(); 
 			con=t.getCon(); 
 		}catch(Exception e){ 
 			out.println(e);