eclipse项目jdbc实例

package basic; import java.awt.Rectangle; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JLabel; import javax.swing.JPanel; import javax.swing.JTextField; import java.sql.*; public class LoginPanel extends JPanel { private static final long serialVersionUID = 1L; private JLabel usenameLabel = null; private JLabel passwordLabel = null; private JTextField passwordTextField = null; private JTextField ResultTextField = null; private JTextField usenameTextField = null; private JButton loginButton = null; /** * This is the default constructor */ public LoginPanel() { super(); initialize(); } /** * This method initializes this * * @return void */ private void initialize() { passwordLabel = new JLabel(); passwordLabel.setText("password"); passwordLabel.setBounds(new Rectangle(35, 80, 65, 15)); usenameLabel = new JLabel(); usenameLabel.setText("usename"); usenameLabel.setBounds(new Rectangle(35, 30, 63, 15)); this.setSize(300, 200); this.setLayout(null); this.add(usenameLabel, null); this.add(passwordLabel, null); this.add(getPasswordTextField(), null); this.add(getResultTextField(), null); this.add(getUsenameTextField(), null); this.add(getLoginButton(), null); } /** * This method initializes passwordTextField * * @return javax.swing.JTextField */ private JTextField getPasswordTextField() { if (passwordTextField == null) { passwordTextField = new JTextField(); passwordTextField.setBounds(new Rectangle(119, 80, 104, 19)); } return passwordTextField; } /** * This method initializes ResultTextField * * @return javax.swing.JTextField */ private JTextField getResultTextField() { if (ResultTextField == null) { ResultTextField = new JTextField(); ResultTextField.setBounds(new Rectangle(119, 150, 106, 19)); } return ResultTextField; } /** * This method initializes usenameTextField * * @return javax.swing.JTextField */ private JTextField getUsenameTextField() { if (usenameTextField == null) { usenameTextField = new JTextField(); usenameTextField.setBounds(new Rectangle(119, 30, 102, 19)); } return usenameTextField; } /** * This method initializes loginButton * * @return javax.swing.JButton */ private JButton getLoginButton() { if (loginButton == null) { loginButton = new JButton(); loginButton.setBounds(new Rectangle(35, 150, 70, 20)); loginButton.setText("Login"); loginButton.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent e) { try{ String un = usenameTextField.getText(); String pw = passwordTextField.getText(); String sql = "select * from lgoin where username='"+un+"' and password='"+pw+"' "; Class.forName("com.mysql.jdbc.Driver"); Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/yukuidb","root","yukui"); /* Statement stmt = conn.createStatement(); ResultSet rs = stmt.executeQuery(sql); */ PreparedStatement pstmt = conn.prepareStatement("select * from login where usename=? and password=?"); pstmt.setString(1, un); pstmt.setString(2, pw); ResultSet rs = pstmt.executeQuery(); if(rs.next()){ ResultTextField.setText("true"); }else{ ResultTextField.setText("false"); } rs.close(); pstmt.close(); conn.close(); }catch(Exception a){a.printStackTrace();} } }); } return loginButton; } }