databean.java

一个聊天系统

package chat;

import java.sql.*;
import java.io.*;

/**
 * 类名：DataBean
 * 描述：完成底层的数据库操作
 */

public class DataBean {
  //驱动
  static final String DbDriver = "sun.jdbc.odbc.JdbcOdbcDriver";
  //连接数据
  static final String strConn="jdbc:odbc:chatroom";
  private Connection dbCon;
  private Statement stl;

  public DataBean()
  {

  }
  //数据库连接操作
  public boolean connect()
  {
    try{
      DriverManager.registerDriver((Driver)(Class.forName(DbDriver).newInstance()));
      dbCon=DriverManager.getConnection(strConn);
      stl=dbCon.createStatement();
    }
    catch(Exception e)
    {
      return false;
    }
    return true;
  }

  //数据库的SQL查询
  public ResultSet openRs(String sql) throws java.sql.SQLException {
    ResultSet rs = stl.executeQuery(sql);
    return (rs);
  }

  //执行SQL语句
  public boolean  executeSql(String sql){
    try{
        stl.execute(sql);
    }catch (Exception e) {
        return false;
    }
    return true ;
  }

  //提供对管理员帐户和密码的合法性检查
  public boolean checkLogin(String user,String password) {
    try{
      String sql="select * from admin_info where admin_name='"
                +user+"'and admin_pwd='"+password+"'";
            ResultSet rs=stl.executeQuery(sql);
        if(rs.next() )
           return true;
        else
           return false;
    }catch (Exception e) {
        return false;
    }
  }

  //利用SQL语句进行数据库更新
  public void update(String strSQL)
  {
    try
    {
      stl.executeUpdate(strSQL);
    }catch(Exception e)
    {
      e.printStackTrace();
    }
  }

  //关闭数据库
  public void close(){
    try {
         dbCon.close();
         stl=null;
         dbCon=null;
    }
    catch (Exception e) {
    }
  }

}