Need to specify class name in environment or system property, or as an applet pa

Need to specify class name in environment or system property, or as an applet parameter, or in an application resource file: ja
请问各位大侠，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
com.datang.exception.ApplicationException是什么原因呢？烦请高手指导指导。一下是出错的代码：
package com.datang.dao.impl;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import com.datang.dao.EmployeeDAO;
import com.datang.exception.ApplicationException;
import com.datang.po.Employee;
import com.datang.po.EmployeeList;
import com.datang.util.DBUtil;

public class EmployeeMySQLDAOImpl implements EmployeeDAO{

public static final String GET_EMPLOYEE_BY_ID="select id,name,sex,hire_date,position,birthday,degree,major,experience 

from t_employee";


public EmployeeList getEmployeeById(String id)throws ApplicationException{
Connection conn=null;
PreparedStatement pstmt=null;
ResultSet rs=null;
EmployeeList emp=new EmployeeList();

try{
conn=DBUtil.getConnection(); <-----从这一句就直接跳转的finally里边了。。
pstmt=conn.prepareStatement(GET_EMPLOYEE_BY_ID);
pstmt.setString(1, id);
rs=pstmt.executeQuery();
while(rs.next()){

emp.setId(rs.getString(1));
emp.setName(rs.getString(2));
emp.setSex(rs.getString(3).equals("0")?"男":"女");
emp.setHire_date(rs.getDate(4));
emp.setPosition(rs.getString(5));
emp.setBirthday(rs.getDate(6));
emp.setDegree(rs.getString(7));
emp.setMajor(rs.getString(8));
emp.setExperience(rs.getString(9));
}
return emp;
}catch(SQLException e){
e.printStackTrace();
return null;
}finally{
DBUtil.close(rs, pstmt, conn);
}
}

public static void main(String[] args){
try {
EmployeeList name=new EmployeeMySQLDAOImpl().getEmployeeById("1");
System.out.println(name);
} catch (ApplicationException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

抛出的异常是：2008-10-24 09:42:45:INFO main com.datang.util.DBUtil - 数据库发生异常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
com.datang.exception.ApplicationException
at com.datang.util.DBUtil.getConnection(DBUtil.java:32)
at com.datang.dao.impl.EmployeeMySQLDAOImpl.getEmployeeById(EmployeeMySQLDAOImpl.java:166)
at com.datang.dao.impl.EmployeeMySQLDAOImpl.main(EmployeeMySQLDAOImpl.java:193)

经检查DBUtil.java ApplicationException.java 都没错，谢谢了！！


[解决办法]
java.naming.factory.initial

那一句跳了，你就再跟进去呗，应该是Class.forName那里出错了，检查一下。