package sfms;import java.awt.*;import java.sql.*;import javax.swing.*;import java.awt.event.*;public class ll extends JFrame implements ActionListener {   JTextField tt1, t2, t3, t4, t5, t6;   JButton b4, b5, b6;   String STNO="100009";   ll() {     super("更新學生檔案");     Container c2 = this.getContentPane();     setBackground(new Color(215, 215, 215));    c2.setLayout(new GridLayout(3, 1));     tt1= new JTextField(50);     t2 = new JTextField(50);     t3 = new JTextField(50);     t4 = new JTextField(50);     t5 = new JTextField(50);     t6 = new JTextField(50);     JPanel pp1=new JPanel();     pp1.add(new JLabel("學號為" + STNO + "學生的檔案"));     c2.add(pp1);     JPanel pp2 = new JPanel(new GridLayout(6,2));     pp2.add(new JLabel("學號"));     tt1.setText(STNO);     pp2.add(tt1);     pp2.add(new JLabel("姓名"));     pp2.add(t2);     pp2.add(new JLabel("性別"));     pp2.add(t3);     pp2.add(new JLabel("系別"));     pp2.add(t4);     pp2.add(new JLabel("地址"));     pp2.add(t5);     pp2.add(new JLabel("電話"));     pp2.add(t6);     c2.add(pp2);     JPanel pp3 = new JPanel(new FlowLayout());     b4 = new JButton("確定");     b5 = new JButton("清除");     b6 = new JButton("退出");     b4.addActionListener(this);     b5.addActionListener(this);     b6.addActionListener(this);     pp3.add(b4);     pp3.add(b5);     pp3.add(b6);     c2.add(pp3);     this.setSize(400,300);     this.addWindowListener(new WindowAdapter() {     public void windowClosing(WindowEvent event) {         shutDown2();          }             }          );  try {       Class.forName("oracle.jdbc.OracleDriver").newInstance();       String url = "jdbc:oracle:thin:@thsspc0792:1521:SFMS";       Connection cn = DriverManager.getConnection(url, "df", "1234");       String str = "select * from DF.FILEINFO where STNO='" + STNO + "'";       PreparedStatement ps = cn.prepareStatement(str);       ResultSet rs = ps.executeQuery();       if (rs.next() == false) {        JOptionPane.showMessageDialog(null, "您輸入的學生號有誤,請重新輸入","輸入錯誤",                                     JOptionPane.YES_NO_OPTION );       }       else {         tt1.setText(rs.getString("STNO"));         t2.setText(rs.getString("SName"));         t3.setText(rs.getString("Gender"));         t4.setText(rs.getString("Department"));         t5.setText(rs.getString("NativePlace"));         t6.setText(rs.getString("TEL"));       }       cn.close();     }     catch (SQLException e) {       System.out.println("Error Code: " + e.getErrorCode());       System.out.println("Message=" + e.getMessage());     }     catch (Exception e) {       e.printStackTrace();     }   }   public void actionPerformed(ActionEvent f) {     if (f.getSource() == b4) {       up();     }     if (f.getSource() == b5) {       tt1.setText("");       tt1.repaint();       t2.setText("");       t2.repaint();       t3.setText("");       t3.repaint();       t4.setText("");       t4.repaint();       t5.setText("");       t5.repaint();       t6.setText("");       t6.repaint();     }     if (f.getSource() == b6) {       shutDown2();     }   }   public void up() {     String s1, s2, s3, s4, s5, s6;     s1 = tt1.getText();     s2 = t2.getText();     s3 = t3.getText();     s4 = t4.getText();     s5 = t5.getText();     s6 = t6.getText();     if (s1.length() == 0) {       JOptionPane.showMessageDialog(null, "沒有輸入學生號");     }     if (s2.length() == 0) {       JOptionPane.showMessageDialog(null, "沒有輸入學生名");     }     if (s3.length() == 0) {       JOptionPane.showMessageDialog(null, "沒有輸入學生性別");     }     if (s4.length() == 0) {       JOptionPane.showMessageDialog(null, "沒有輸入學生系別");     }     if (s5.length() == 0) {       JOptionPane.showMessageDialog(this, "沒有輸入學生地址");     }     if (s6.length() == 0) {       JOptionPane.showMessageDialog(null, "沒有輸入學生電話");     }     else {       try {         Class.forName("oracle.jdbc.OracleDriver").newInstance();         String url = "jdbc:oracle:thin:@localhost:1521:SFMS";         Connection cn = DriverManager.getConnection(url, "df", "1234");         String str = "update DF.FILEINFO SET SNAME='" + s2 + "',GENDER='" + s3 + "',DEPARTMENT='" + s4 + "',NATIVEPLACE='" + s5 + "',TEL='"+s6+"' WHERE STNO='"+s1+"' ";         /*   "SNAME='" + s2 + "',"+            "GENDER='" + s3 + "',"+            "DEPARTMENT='" + s4 + "',"+            "NATIVEPLACE='" + s5 + "',"+*/         /*       +            "SET"+            "TEL='12324'"+            "WHERE STNO='100009'";          */         PreparedStatement ps = cn.prepareStatement(str);       ps.setString(1, s1);         System.out.println("s1="+s1);         ps.setString(2, s2);       ps.setString(3, s3);         System.out.println("s2="+s2);         ps.setString(4, s4);         ps.setString(5, s5);         ps.setString(6, s6);        ps.executeQuery(str);         cn.close();         JOptionPane.showMessageDialog(null, "更新成功!");       }       catch (SQLException e) {         JOptionPane.showMessageDialog(null, "更新失敗!");       }       catch (Exception e) {                      e.printStackTrace();         }     }   }   public void shutDown2() {     System.exit(0);   }    public static void main(String[] args) {     ll rr = new ll();      rr.setVisible(true);    }}