数据库课程设计(含数据库源码).7z

package DAO; import java.awt.GridLayout; import java.awt.event.*; import java.sql.*; import javax.swing.*; import com.mysql.jdbc.PreparedStatement; import Main.DBMain; public class AddStudent extends JFrame { static int colNum = 0; static String[] col = new String[15]; JLabel lab_No, lab_Name, lab_Class, lab_Pwd; JTextField tf_No, tf_Name, tf_Class, tf_Pwd; String getStuNo = ""; String sql = ""; boolean stuNoIsExist = false; public AddStudent() { setTitle("添加学生"); JPanel pan_No = new JPanel(); JPanel pan_Name = new JPanel(); JPanel pan_Class = new JPanel(); JPanel pan_Pwd = new JPanel(); setSize(300, 500); colNum = getCol(); setLocationRelativeTo(null); lab_No = new JLabel("学号"); tf_No = new JTextField(15); tf_No.addKeyListener(new KeyAdapter() { public void keyTyped(KeyEvent e) { char c = e.getKeyChar(); if (Character.isDigit(c)) { return; } else { //e.consume();// 清除输入的非数字内容 } } }); pan_No.add(lab_No); pan_No.add(tf_No); lab_Name = new JLabel("姓名"); tf_Name = new JTextField(15); pan_Name.add(lab_Name); pan_Name.add(tf_Name); lab_Class = new JLabel("班级"); tf_Class = new JTextField(15); tf_Class.addKeyListener(new KeyAdapter() { public void keyTyped(KeyEvent e) { char c = e.getKeyChar(); if (Character.isDigit(c)) { return; } else { e.consume();// 清除输入的非数字内容 } } }); pan_Class.add(lab_Class); pan_Class.add(tf_Class); lab_Pwd = new JLabel("密码"); tf_Pwd = new JTextField(15); tf_Pwd.addKeyListener(new KeyAdapter() { public void keyPressed(KeyEvent e) { if (e.getKeyCode() == KeyEvent.VK_ENTER) isExist();// 判断学号是否已经存在数据库中 if (!stuNoIsExist) { addStu(); // 数据库中不存在输入的学号，进行添加操作 tf_No.setText(""); tf_Name.setText(""); tf_Class.setText(""); tf_Pwd.setText(""); } else { JOptionPane.showMessageDialog(null, "该学号已经存在！"); } } }); pan_Pwd.add(lab_Pwd); pan_Pwd.add(tf_Pwd); JPanel pan_Btn = new JPanel(); JButton btn_OK = new JButton("确定"); // 添加按钮监听，点击进行添加学生 btn_OK.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { isExist();// 判断学号是否已经存在数据库中 if (!stuNoIsExist) { addStu();// 数据库中不存在输入的学号，进行添加操作 } else { JOptionPane.showMessageDialog(null, "该学号已经存在！"); } } }); JButton btn_Cancle = new JButton("取消"); // 点击取消则隐藏该窗口 btn_Cancle.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { setVisible(false); } }); pan_Btn.add(btn_OK); pan_Btn.add(btn_Cancle); getContentPane().setLayout(new GridLayout(5, 1)); getContentPane().add(pan_No); getContentPane().add(pan_Name); getContentPane().add(pan_Class); getContentPane().add(pan_Pwd); getContentPane().add(pan_Btn); pack(); setVisible(true); } public static int getCol() { int num = 0; Connection conn = null; java.sql.PreparedStatement pstmt = null; ResultSet rs; try { conn = DBMain.getConnection(); String sql = "select * from stu_info"; pstmt = conn.prepareStatement(sql); rs = pstmt.executeQuery(sql); ResultSetMetaData colName = rs.getMetaData(); num = colName.getColumnCount(); if (rs.next()) { int i, j; for (i = 0, j = 1; i < colNum && j <= colNum; i++, j++) col[i] = colName.getColumnName(j); } } catch (Exception e) { e.printStackTrace(); } return num; } public void isExist() { getStuNo = tf_No.getText().trim(); java.sql.PreparedStatement pstmt = null; Connection conn1 = null; ResultSet rs = null; if (!("".equals(getStuNo))) { // 学号不为空，进入数据库查询该学号是否已经存在 try { conn1 = DBMain.getConnection(); sql = "select * from stu_info where stuNo=?"; pstmt = conn1.prepareStatement(sql); pstmt.setString(1, getStuNo); rs = pstmt.executeQuery(); if (rs.next()) { stuNoIsExist = true; } else { stuNoIsExist = false; } } catch (Exception e) { e.printStackTrace(); } } else { JOptionPane.showMessageDialog(null, "学号为空，请重新输入！"); } } private void addStu() { Connection conn2 = null; java.sql.PreparedStatement pstmt = null; // 获取各文本框中输入的数据 String name = tf_Name.getText().trim(); String clas = tf_Class.getText().trim(); String pwd = tf_Pwd.getText().trim(); if (!("".equals(name)) || !("".equals(clas)) || !("".equals(pwd))) { try { conn2 = DBMain.getConnection(); sql = "insert into stu_info(stuNo,stuName,classNo,stuPwd) values (?,?,?,?)";// 添加语句 pstmt = conn2.prepareStatement(sql); pstmt.setString(1, getStuNo); pstmt.setString(2, name); pstmt.setString(3, clas); pstmt.setString(4, pwd); pstmt.executeUpdate();// 添加并更新信息 JOptionPane.showMessageDialog(null, "添加学生成功！"); setVisible(false); } catch (Exception e) { e.printStackTrace(); } } else { JOptionPane.showMessageDialog(null, "信息不完整，请重新输入！"); } } }