mysql-数据库MYSQL连接成功,可是遍历next()结果不是我想要呀!!!
mysql遍历exception数据库
事件监听中要检验JTextField的内容是否与数据库中一致,一致则登录成功,否则登录失败,但是现在无论JTextField的内容如何,都是输出登录失败,求大神解救啊。。。
import java.sql.*;
import javax.swing.JOptionPane;
public class MysqlJdbc {
public User user= new User();
<code> public void Login(User user){ String url=null; Connection con=null; Statement stmt=null; ResultSet rs=null; // String qu="SELECT * FROM login where UserName='"+user+"';"; try{ String a=user.getUserName(); String b=user.getPassword(); /* * 通过mySQL专用引擎获得连接对象 * locahost为IP地址,3306为端口号,DatabaseName为安装的一个数据库服务名 */ url="jdbc:mysql:localhost:3306;DatabaseName=hou"; Class.forName("com.mysql.jdbc.Driver"); System.out.println("连接数据库成功!"); con =DriverManager.getConnection( "jdbc:mysql://localhost:3306/hou","root","123456"); stmt=con.createStatement(); String query="select UserName,Password from login where UserName='"+a+"' and Password='"+b+"';"; //向数据库提交查询语句,获得一个被rs引用的结果集 rs=stmt.executeQuery(query); //对结果集进行遍历,显示其内容 if (rs.next()) { JOptionPane.showMessageDialog(null,"登录成功" ); } else{ JOptionPane.showMessageDialog(null, "登录失败"); } } catch (Exception e) { System.out.print("连接数据库失败!"); e.printStackTrace(); } finally{ try{ if(rs!=null){ rs.close();} if(stmt!=null){ stmt.close();} if(con!=null){ con.close();} } catch(SQLException e){} } }</code>
}
btnLogin.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String UserName=textUserName.getText();
String Password=passwordField.getText();
User user=new User();
user.setUserName(UserName);
user.setPassword(Password);
<code> MysqlJdbc mysqlJdbc=new MysqlJdbc(); mysqlJdbc.Login(user); } }</code>

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