draw.java

界面不错的东西

/*************光大银行储户提款****************/
import java.awt.*;
import java.awt.event.*;
import java.sql.*;
import javax.swing.*;
import java.math.*;
class Draw extends JFrame implements ActionListener{
   Connection Con=null;
   Statement  Stmt=null;
   JLabel lb=new JLabel("尊敬的储户你好! ");
   JLabel lb_msg=new JLabel("感谢你选择光大银行!");
   JLabel lb_input_account_no=new JLabel("请输入储户账号:");  //刷卡机自动读取
   JTextField con_acco=new JTextField(15);
   JLabel lb_input_draw_sum=new JLabel("请输入你要提取的金额:");
   JTextField draw_sum=new JTextField(15);
   JLabel lb_input_acco_pwd=new JLabel("请输入你的账户密码:");
   JPasswordField con_pwd=new JPasswordField(15);
   JButton bt_ack=new JButton("确认");
   JButton bt_can=new JButton("取消");
   Draw(){  
   super("光大银行欢迎你!感谢你对光大银行的支持!");
   this.setBounds(250,250,450,200);
   this.setVisible(true);
   Container con=getContentPane();
   con.setLayout(new FlowLayout());
   con.setBounds(250,250,450,200);
   JPanel p=new JPanel();
   p.setLayout(new GridLayout(5,2));
   p.add(lb); p.add(lb_msg);
   p.add(lb_input_account_no); p.add(con_acco);
   p.add(lb_input_draw_sum);   p.add(draw_sum);
   p.add(lb_input_acco_pwd);   p.add(con_pwd);
   p.add(bt_ack);
   p.add(bt_can);
   bt_ack.addActionListener(this);
   bt_can.addActionListener(this);
   con.add(p,"CENTER");
   validate();
  }
  public void actionPerformed(ActionEvent e){
   if(e.getSource()==bt_ack)
   {
     if(con_acco.getText().trim().equals("")||draw_sum.getText().trim().equals("")||con_pwd.getText().trim().equals("")) 
        {
        JOptionPane.showMessageDialog(this,"账号与取款金额、密码不能为空!","警告",JOptionPane.WARNING_MESSAGE);
        } //判断输入框不能为空
     else
        {
         con_drawing();
        }
   }
   if(e.getSource()==bt_can)
   {
    dispose();
   }
 }
  private void con_drawing(){
    //con_drawing函数完成用户取款的处理
    String _con_acco,_con_pwd,_con_drawsum,temp;
    _con_drawsum=draw_sum.getText().trim();
    float _draw_sum,remain;
    _con_acco="'"+con_acco.getText().trim()+"'";
    _con_pwd="'"+con_pwd.getText().trim()+"'";
    _draw_sum=Float.parseFloat(_con_drawsum); //可能出现问题
    try{Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");} 
    catch(ClassNotFoundException e){System.out.println("DBClassNotFoundException:"+e.getMessage());}
   try{
        Con=DriverManager.getConnection("jdbc:odbc:Bankdb","","");
        Stmt=Con.createStatement();
        temp="select * from consumer where con_acco='"+con_acco.getText().trim()+"'"+"and con_pwd='"+con_pwd.getText().trim()+"'";            
        ResultSet rs=Stmt.executeQuery(temp); 
        boolean boo=false;
     if(rs.next())  //查到该用户，否则该用户不存在，提示出错信息。
        {//查到的数据为有效数据的前一行,首先读取用户的账户现余金额，判断是否超支；
         //超支则报错，否则交易成功，用户提取款项；账户金额减少。
          boo=true;
          remain=Float.parseFloat(rs.getString("con_rema"));
          if(remain >= _draw_sum)
           {
             remain=remain - _draw_sum;
             String tmp="update consumer set con_rema='"+remain+"'"+"WHERE con_acco="+_con_acco;   //一定要仔细认真，账户号写错:con_rema写成了con_remain
             System.out.println(tmp);
             Stmt.executeUpdate(tmp);
         JOptionPane.showMessageDialog(this,"请接收你要提取的现金!\n 你的帐户余额为:'"+remain+"'","恭喜",JOptionPane.WARNING_MESSAGE);
         dispose();
         }
         else
          {
          JOptionPane.showMessageDialog(this,"你的余额已不足!","温馨提示",JOptionPane.WARNING_MESSAGE);
          dispose();
          }
        }
      else
        {
        JOptionPane.showMessageDialog(this,"你输入的用户不存在!或密码不正确,请查证!","警告",JOptionPane.WARNING_MESSAGE);
        }
    Con.close();
      }catch(SQLException e_6){System.out.println("SQLException:"+e_6.getMessage());}
   }
}