关于JAVABEAN的问题(用户登陆)

Question

编写一个JAVABEAN 实现用户登陆时候 密码与数据库比较 然后正确登陆
是怎么样在 *.JAVA中 写抛出异常这个过程?

Answer 1

在你需要抛出异常的地方throw New Exception("抛出异常");

Answer 2

try{
登陆的逻辑
}
catch(SQLException e){
e.printStackTrace();}

Answer 3

也可以这样
try{
登陆的逻辑
错误时：throw new Exception;
}
catch(SQLException e){
e.printStackTrace("出错信息");}
  

Answer 4

package com.ly.application;import java.sql.*;
import com.ly.common.*;
//import java.text.*;/**
 *Function Detail : 用户登录
 Date            : 2006-8-13
 Author          : liaohaiying
 Version         : longying 1.0
 */public class LogonService extends WebServices{  private ResultSet mobjRs = null;
    public LogonService() throws Exception
    {
        super();
    }
    
public SysUser getLogonSysUser(String pstrLogonName,String pstrPassWord) throws Exception
{
Test1 pobjTest1 = new Test1();
    String pstrtest1 = pobjTest1.getTest1();
SysUser pobjSysUser = null;
SysUserServices pobjSysUserServices = new SysUserServices();
//MD5 pobjMD5=new MD5();
//String PassWord=pobjMD5.getMD5ofStr(pobjSysUser.getPassWord());
String pstrSql = "SELECT * FROM ly_user WHERE logonName = '"+pstrLogonName+"' AND passwd ='"+pstrPassWord+"'";
ResultSet mobjRs = mobjDatabase.getResultSetForwardOnly(pstrSql);
if(mobjRs.next())
{
pobjSysUser = new SysUser();
pobjSysUser.setID(mobjRs.getInt("ID"));//正确就把ID写入pobjSysUser
pobjSysUser.setUserName(mobjRs.getString("userName"));
pobjSysUser.setLogonName(mobjRs.getString("logonName"));
pobjSysUser.setPassWord(mobjRs.getString("passwd"));
pobjSysUser.setUserName(mobjRs.getString("username"));
pobjSysUser.setJob(mobjRs.getString("job"));
pobjSysUser.setPurview(mobjRs.getString("purview"));
pobjSysUser.setTelephone(mobjRs.getString("phone"));
pobjSysUser.setVisit_dt(mobjRs.getString("visit_dt"));
}
mobjRs.close();
if(pobjTest1.chktest1(pstrtest1))
{
if(!pobjTest1.chktest2())
{
if(!pobjTest1.chktest3())
{
pobjSysUser = new SysUser();
pobjSysUser.setID(0);//不符合上述条件就把0写入pobjSysUser
}
}
}
else
{
if(!pobjTest1.addtest1())
{
pobjSysUser = new SysUser();
pobjSysUser.setID(-1);//不符合上述条件就把-1写入pobjSysUser
}
}
if(!pobjSysUserServices.getSysUsertime())
{
pobjSysUser = new SysUser();
pobjSysUser.setID(-2);//不符合上述条件就把-2写入pobjSysUser
}
return pobjSysUser;//返回pobjSysUser
}
}
前台页面
<% 
if(request.getMethod().equals("POST"))
    {
        String pstrLogonName  = request.getParameter("userName"); 
        String pstrPassWord = request.getParameter("passWd");
        SysUser pobjSysUser = new SysUser();
        LogonService pobjLogonService = new LogonService();
        pobjSysUser = pobjLogonService.getLogonSysUser(pstrLogonName,pstrPassWord); 
        if(pobjSysUser!=null)
        {
            if(pobjSysUser.getID()==-2)
            {
           String pstrScript9 = "<script language='javascript'>alert('系统时间不正确！请调整后再登陆');window.opener=null;window.close();";
       pstrScript9 +="</script>";
       out.print(pstrScript9);
            }
            else
            {
            if(pobjSysUser.getID()!=0)
            {
            if(pobjSysUser.getID()!=-1)
            {
            //设置SESSIN的值!
            session.setAttribute("SysUserID",String.valueOf(pobjSysUser.getID()));
            session.setAttribute("SysUserName",pobjSysUser.getUserName());
            session.setAttribute("SysUserLogonName",pobjSysUser.getLogonName());
         }
         else
         {
          out.print("登陆系统不成功");
         }
         }
         else
         {
           String pstrScript = "<script language='javascript'>alert('已过100天的试用期，如果您还将继续使用本软件，请于龙鹰软件工作室联系!');window.opener=null;window.close();";
       pstrScript +="</script>";
       out.print(pstrScript);
         }
         }
        }
        else
        {
      String pstrScript1 = "<script language='javascript'>alert('用户名与密码不正确，请重新输入!');";
       pstrScript1 +="</script>";
       out.print(pstrScript1);
        }
     }
     else
     {
        session.removeAttribute("SysUserID");
        session.removeAttribute("SysUserName");
        session.removeAttribute("SysUserLogonName");
     } 
%>