Java能，jsp不能连接sql sever2005 - Java / Web 开发

注：我已经把驱动程序放在网站的ＷＥＢ—INFO的lib下了
tomcat 报错：The server encountered an internal error () that prevented it from fulfilling this request.

Java代码：
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import java.sql.*;
import java.util.*; 
public class test {
public static void main(String[] srg) {
  String driverName = "com.microsoft.sqlserver.jdbc.SQLServerDriver"; //加载JDBC驱动
  String dbURL = "jdbc:sqlserver://localhost:1433; DatabaseName=test"; //连接服务器和数据库test
  String userName = "sa"; //默认用户名
  String userPwd = "yjs"; //密码
  String dbName="test";
  String tableName="student";
  Connection dbConn;

  try {
  Class.forName(driverName).newInstance();
  dbConn = DriverManager.getConnection(dbURL, userName, userPwd);
  System.out.println("Connection Successful!"); //如果连接成功 控制台输出Connection Successful!
  Statement stmt=dbConn.createStatement();
  String sql="select StuId,StuName from student;";
  ResultSet rs=stmt.executeQuery(sql);
  while(rs.next())
  { String id=rs.getString("StuId"); //取出id列的内容
String name=rs.getString("StuName");