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这是一个学生信息管理系统,学生信息主要包括:学号,姓名,性别,出生日期,班级;暂时就只有这些信息,若后续需要,可以相应的进行添加。
该项目主要采用的技术是 Java GUI 设计,这个地方主要用 Java 工具 windowsbuilder 进行布局,(windowsbuilder没有安装或者不会安装的,可以看看我的这篇博客 Eclipse 安装 windowbuilder插件 ),MySql 数据库(MySql 数据库没有安装的 或者数据库使用软件 Navicat 没有安装的可以看看我的这篇博客 2021 MySql 8.0.26 安装教程(最详细的傻瓜教程) ),以及使用 Java 中的 JDBC 将数据库链接起来。
由于在项目中没有创建学生数据库的功能,所以学生数据库必须要先建立好,下面给出如何建立好MySQL学生数据库的相关代码 + 图片
-- 创建数据库 CREATE DATABASE niit DEFAULT CHARACTER SET utf8mb4; SHOW DATABASES; -- 使用数据库niit USE niit; -- 创建表Student CREATE TABLE Student ( ID INT PRIMARY KEY, NAME VARCHAR(4), GENDER CHAR(1), DOB DATE, BATCH INT ); -- 插入记录 INSERT INTO Student VALUES (1,'独孤求败','男','1988-1-2',1), (2,'周芷若','女','1988-12-3',1), (3,'金毛狮王','男','1978-11-1',1), (4,'蒙挚','男','1989-2-5',2), (5,'夏春','女','1998-4-3',2), (6,'梅长苏','男','1999-12-6',2); -- 查看表中所有记录 语法:select * from 表名 SELECT * FROM Student;
主页面
添加学生
修改信息
删除学生
查询信息
主页面
package studentsmanager; import java.awt.Color; import java.awt.EventQueue; import java.awt.Font; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; import javax.swing.border.EmptyBorder; import java.awt.event.ActionListener; import java.awt.event.ActionEvent; public class MainFrame extends JFrame { private JPanel contentPane; /** * Launch the application. */ // 有了main函数才可以单独运行 public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { public void run() { try { MainFrame frame = new MainFrame(); frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } /** * Create the frame. */ public MainFrame() { // 设置大小不可改变 setResizable(false); // 设置标题 setTitle("学生管理系统"); // 由于这是主页面,所有当主页面关闭的时候,程序就直接退出 setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // setBounds(int x,int y,int width,int height); // x 和 y 是窗口打开时的位置 // width 和 height 是窗口打宽度和高度 setBounds(100, 100, 450, 350); // setLocationRelativeTo(c) // 设置窗口相对于 c 的位置,当 c 为空或者 null 时,默认为是相对于屏幕中央 setLocationRelativeTo(null); // 实例化一个 pane contentPane = new JPanel(); contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); setContentPane(contentPane); contentPane.setLayout(null); JLabel lblNewLabel = new JLabel("学生管理系统"); lblNewLabel.setForeground(Color.RED); lblNewLabel.setFont(new Font("宋体", Font.BOLD, 25)); lblNewLabel.setBounds(140, 10, 163, 44); contentPane.add(lblNewLabel); JButton addButton = new JButton("添加学生"); // addActionListener 注册监听器 addButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { // 设置新窗口可见 new AddFrame().setVisible(true); } }); addButton.setFont(new Font("宋体", Font.PLAIN, 18)); addButton.setBounds(167, 64, 114, 37); contentPane.add(addButton); JButton changeButton = new JButton("修改信息"); changeButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { // 同上 new ChangeFrame().setVisible(true); } }); changeButton.setFont(new Font("宋体", Font.PLAIN, 18)); changeButton.setBounds(167, 121, 114, 37); contentPane.add(changeButton); JButton deleteButton = new JButton("删除学生"); deleteButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { // 同上 new DeleteFrame().setVisible(true); } }); deleteButton.setFont(new Font("宋体", Font.PLAIN, 18)); deleteButton.setBounds(167, 180, 114, 37); contentPane.add(deleteButton); JButton queryButton = new JButton("查询信息"); queryButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { // 同上 new QueryFrame().setVisible(true); } }); queryButton.setFont(new Font("宋体", Font.PLAIN, 18)); queryButton.setBounds(167, 240, 114, 37); contentPane.add(queryButton); } }
添加学生
package studentsmanager; import java.awt.EventQueue; import java.awt.Font; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.sql.SQLException; import javax.swing.BoxLayout; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JTextField; import javax.swing.border.EmptyBorder; public class AddFrame extends JFrame { private JPanel contentPane; private JTextField idField; private JTextField nameField; private JTextField genderField; private JTextField dobField; private JTextField batchField; /** * Launch the application. */ public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { public void run() { try { AddFrame frame = new AddFrame(); frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } /** * Create the frame. */ public AddFrame() { // 和前面类似 setResizable(false); setTitle("添加学生"); // 这个地方,添加学生只是这个程序的一部分,所以当关闭这部分的时候,程序不直接退出,只是关闭该部分程序 setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); setBounds(100, 100, 450, 470); setLocationRelativeTo(null); contentPane = new JPanel(); contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); setContentPane(contentPane); contentPane.setLayout(new BoxLayout(contentPane, BoxLayout.Y_AXIS)); JPanel panel = new JPanel(); contentPane.add(panel); panel.setLayout(null); JLabel TitleLabel = new JLabel("请输入新学生的信息:"); TitleLabel.setFont(new Font("宋体", Font.BOLD, 20)); TitleLabel.setBounds(71, 34, 208, 45); panel.add(TitleLabel); JLabel idLabel = new JLabel("学号:"); idLabel.setFont(new Font("宋体", Font.PLAIN, 16)); idLabel.setBounds(71, 105, 50, 30); panel.add(idLabel); idField = new JTextField(); idField.setBounds(143, 99, 240, 45); panel.add(idField); idField.setColumns(10); JLabel nameLabel = new JLabel("姓名:"); nameLabel.setFont(new Font("宋体", Font.PLAIN, 16)); nameLabel.setBounds(71, 160, 50, 30); panel.add(nameLabel); nameField = new JTextField(); nameField.setColumns(10); nameField.setBounds(143, 154, 240, 45); panel.add(nameField); JLabel genderLabel = new JLabel("性别:"); genderLabel.setFont(new Font("宋体", Font.PLAIN, 16)); genderLabel.setBounds(71, 215, 50, 30); panel.add(genderLabel); genderField = new JTextField(); genderField.setColumns(10); genderField.setBounds(143, 209, 240, 45); panel.add(genderField); JLabel dobLabel = new JLabel("出生日期:"); dobLabel.setFont(new Font("宋体", Font.PLAIN, 16)); dobLabel.setBounds(41, 270, 80, 30); panel.add(dobLabel); dobField = new JTextField(); dobField.setColumns(10); dobField.setBounds(143, 264, 240, 45); panel.add(dobField); JLabel batchLabel = new JLabel("班级:"); batchLabel.setFont(new Font("宋体", Font.PLAIN, 16)); batchLabel.setBounds(71, 325, 50, 30); panel.add(batchLabel); batchField = new JTextField(); batchField.setColumns(10); batchField.setBounds(143, 319, 240, 45); panel.add(batchField); JButton addButton = new JButton("添加"); // 添加鼠标监听事件 addButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { // 先取出数据 // getText() 返回字符串类型的 // Integer.parseInt 数据类型转换 int id = Integer.parseInt(idField.getText()); String nameString = nameField.getText(); String genderString = genderField.getText(); String dobfieldString = dobField.getText(); int batch = Integer.parseInt(batchField.getText()); // 输出一下学生的信息,方便修改 System.out.println(id + "\t" + nameString + "\t" + genderString + "\t" + dobfieldString + "\t" + batch); // SQLHelp 是自己写的一个工具类 SQLHelp sqlHelp = new SQLHelp(); try { // 调用添加学生信息的方法 sqlHelp.addStudent(id, nameString, genderString, dobfieldString, batch); // 弹出对话框,提示用户添加成功 JOptionPane.showMessageDialog(AddFrame.this, "添加成功!"); } catch (SQLException e1) { // 这里捕获一下异常,因为学生的学号是唯一的,所以当学号已经存在的时候,提示用户,该学生信息已存在 // 异常代码为 23000 if(e1.getSQLState().equals("23000")) { JOptionPane.showMessageDialog(AddFrame.this, "添加失败!该学生已存在"); } e1.printStackTrace(); } } }); addButton.setFont(new Font("宋体", Font.PLAIN, 18)); addButton.setBounds(182, 389, 97, 33); panel.add(addButton); } }
添加成功:
添加失败:
修改信息
package studentsmanager; import java.awt.EventQueue; import java.awt.Font; import javax.swing.BoxLayout; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JTextField; import javax.swing.border.EmptyBorder; import java.awt.event.ActionListener; import java.sql.SQLException; import java.awt.event.ActionEvent; public class ChangeFrame extends JFrame { private JPanel contentPane; private JTextField idField; private JTextField nameField; private JTextField genderField; private JTextField dobField; private JTextField batchField; private JTextField searchField; /** * Launch the application. */ public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { public void run() { try { ChangeFrame frame = new ChangeFrame(); frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } /** * Create the frame. */ public ChangeFrame() { setResizable(false); setTitle("修改信息"); setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); setBounds(100, 100, 450, 470); setLocationRelativeTo(null); contentPane = new JPanel(); contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); setContentPane(contentPane); contentPane.setLayout(new BoxLayout(contentPane, BoxLayout.Y_AXIS)); JPanel panel = new JPanel(); contentPane.add(panel); panel.setLayout(null); JLabel lblNewLabel = new JLabel("请输入要修改的学生的学号:"); lblNewLabel.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel.setBounds(71, 0, 208, 29); panel.add(lblNewLabel); JLabel lblNewLabel_1 = new JLabel("学号:"); lblNewLabel_1.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1.setBounds(71, 105, 50, 30); panel.add(lblNewLabel_1); idField = new JTextField(); idField.setEditable(false); idField.setBounds(143, 99, 240, 45); panel.add(idField); idField.setColumns(10); JLabel lblNewLabel_1_1 = new JLabel("姓名:"); lblNewLabel_1_1.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1_1.setBounds(71, 160, 50, 30); panel.add(lblNewLabel_1_1); nameField = new JTextField(); nameField.setColumns(10); nameField.setBounds(143, 154, 240, 45); panel.add(nameField); JLabel lblNewLabel_1_1_1 = new JLabel("性别:"); lblNewLabel_1_1_1.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1_1_1.setBounds(71, 215, 50, 30); panel.add(lblNewLabel_1_1_1); genderField = new JTextField(); genderField.setColumns(10); genderField.setBounds(143, 209, 240, 45); panel.add(genderField); JLabel lblNewLabel_1_1_1_1 = new JLabel("出生日期:"); lblNewLabel_1_1_1_1.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1_1_1_1.setBounds(41, 270, 80, 30); panel.add(lblNewLabel_1_1_1_1); dobField = new JTextField(); dobField.setColumns(10); dobField.setBounds(143, 264, 240, 45); panel.add(dobField); JLabel lblNewLabel_1_1_1_2 = new JLabel("班级:"); lblNewLabel_1_1_1_2.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1_1_1_2.setBounds(71, 325, 50, 30); panel.add(lblNewLabel_1_1_1_2); batchField = new JTextField(); batchField.setColumns(10); batchField.setBounds(143, 319, 240, 45); panel.add(batchField); JButton changeButton = new JButton("修改"); changeButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent arg0) { int id = Integer.parseInt(searchField.getText()); String nameString = nameField.getText(); String gendeString = genderField.getText(); String dobString = dobField.getText(); int batch = Integer.parseInt(batchField.getText()); SQLHelp sqlHelp = new SQLHelp(); try { sqlHelp.changeStudent(id, nameString, gendeString, dobString, batch); JOptionPane.showMessageDialog(ChangeFrame.this, "修改成功!"); } catch (SQLException e) { JOptionPane.showMessageDialog(ChangeFrame.this, "修改失败!"); e.printStackTrace(); } } }); changeButton.setFont(new Font("宋体", Font.PLAIN, 18)); changeButton.setBounds(182, 389, 97, 33); panel.add(changeButton); searchField = new JTextField(); searchField.setBounds(71, 39, 208, 45); panel.add(searchField); searchField.setColumns(10); JButton searchButton = new JButton("查找"); searchButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e){ int id = Integer.parseInt(searchField.getText()); try { SQLHelp sqlHelp = new SQLHelp(); Student student = sqlHelp.queryStudent(id); if(student != null) { // id 是直接读入的,所以就不需要从数据库中读出了 idField.setText(String.valueOf(id)); nameField.setText(student.getName()); genderField.setText(student.getGender()); dobField.setText(student.getDob()); batchField.setText(String.valueOf(student.getBatch())); } else { JOptionPane.showMessageDialog(ChangeFrame.this, "无此用户"); } } catch (SQLException e1) { e1.printStackTrace(); } } }); searchButton.setFont(new Font("宋体", Font.PLAIN, 18)); searchButton.setBounds(289, 42, 97, 39); panel.add(searchButton); } }
修改前查询到学生信息
修改成功
修改失败
失败的情况是数据链接出现了问题
未查询到学生信息
删除学生
package studentsmanager; import java.awt.EventQueue; import java.awt.Font; import javax.swing.BoxLayout; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JTextField; import javax.swing.border.EmptyBorder; import java.awt.event.ActionListener; import java.sql.SQLException; import java.awt.event.ActionEvent; public class DeleteFrame extends JFrame { private JPanel contentPane; private JTextField idField; private JTextField nameField; private JTextField genderField; private JTextField dobField; private JTextField batchField; private JTextField searchField; /** * Launch the application. */ public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { public void run() { try { DeleteFrame frame = new DeleteFrame(); frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } /** * Create the frame. */ public DeleteFrame() { setResizable(false); setTitle("删除学生"); setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); setBounds(100, 100, 450, 470); setLocationRelativeTo(null); contentPane = new JPanel(); contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); setContentPane(contentPane); contentPane.setLayout(new BoxLayout(contentPane, BoxLayout.Y_AXIS)); JPanel panel = new JPanel(); contentPane.add(panel); panel.setLayout(null); JLabel lblNewLabel = new JLabel("请输入要删除的学生的学号:"); lblNewLabel.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel.setBounds(71, 0, 208, 29); panel.add(lblNewLabel); JLabel lblNewLabel_1 = new JLabel("学号:"); lblNewLabel_1.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1.setBounds(71, 105, 50, 30); panel.add(lblNewLabel_1); idField = new JTextField(); idField.setEditable(false); idField.setBounds(143, 99, 240, 45); panel.add(idField); idField.setColumns(10); JLabel lblNewLabel_1_1 = new JLabel("姓名:"); lblNewLabel_1_1.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1_1.setBounds(71, 160, 50, 30); panel.add(lblNewLabel_1_1); nameField = new JTextField(); nameField.setColumns(10); nameField.setBounds(143, 154, 240, 45); panel.add(nameField); JLabel lblNewLabel_1_1_1 = new JLabel("性别:"); lblNewLabel_1_1_1.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1_1_1.setBounds(71, 215, 50, 30); panel.add(lblNewLabel_1_1_1); genderField = new JTextField(); genderField.setColumns(10); genderField.setBounds(143, 209, 240, 45); panel.add(genderField); JLabel lblNewLabel_1_1_1_1 = new JLabel("出生日期:"); lblNewLabel_1_1_1_1.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1_1_1_1.setBounds(41, 270, 80, 30); panel.add(lblNewLabel_1_1_1_1); dobField = new JTextField(); dobField.setColumns(10); dobField.setBounds(143, 264, 240, 45); panel.add(dobField); JLabel lblNewLabel_1_1_1_2 = new JLabel("班级:"); lblNewLabel_1_1_1_2.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1_1_1_2.setBounds(71, 325, 50, 30); panel.add(lblNewLabel_1_1_1_2); batchField = new JTextField(); batchField.setColumns(10); batchField.setBounds(143, 319, 240, 45); panel.add(batchField); JButton deleteButton = new JButton("删除"); deleteButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { int id = Integer.parseInt(searchField.getText()); try { SQLHelp sqlHelp = new SQLHelp(); sqlHelp.deletestudent(id); JOptionPane.showMessageDialog(DeleteFrame.this, "删除成功!"); } catch (SQLException e1) { JOptionPane.showMessageDialog(DeleteFrame.this, "删除失败"); e1.printStackTrace(); } } }); deleteButton.setFont(new Font("宋体", Font.PLAIN, 18)); deleteButton.setBounds(182, 389, 97, 33); panel.add(deleteButton); searchField = new JTextField(); searchField.setBounds(71, 39, 208, 45); panel.add(searchField); searchField.setColumns(10); JButton searchButton = new JButton("查找"); searchButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent arg0) { int id = Integer.parseInt(searchField.getText()); try { SQLHelp sqlHelp = new SQLHelp(); Student student = sqlHelp.queryStudent(id); if(student != null) { idField.setText(String.valueOf(id)); nameField.setText(student.getName()); genderField.setText(student.getGender()); dobField.setText(student.getDob()); batchField.setText(String.valueOf(student.getBatch())); } else { JOptionPane.showMessageDialog(DeleteFrame.this, "无此学生"); } } catch (SQLException e) { e.printStackTrace(); } } }); searchButton.setFont(new Font("宋体", Font.PLAIN, 18)); searchButton.setBounds(289, 42, 97, 39); panel.add(searchButton); } }
删除成功
删除失败
删除失败的时候是数据库链接出现了问题
查询到学生信息
未查询到学生
查询信息
package studentsmanager; import java.awt.EventQueue; import java.awt.Font; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.sql.SQLException; import javax.swing.BoxLayout; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JTextField; import javax.swing.border.EmptyBorder; public class QueryFrame extends JFrame { private JPanel contentPane; private JTextField idField; private JTextField nameField; private JTextField genderField; private JTextField dobField; private JTextField batchField; private JTextField searchField; /** * Launch the application. */ public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { public void run() { try { QueryFrame frame = new QueryFrame(); frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } /** * Create the frame. */ public QueryFrame() { setResizable(false); setTitle("查询信息"); setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); setBounds(100, 100, 450, 470); setLocationRelativeTo(null); contentPane = new JPanel(); contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); setContentPane(contentPane); contentPane.setLayout(new BoxLayout(contentPane, BoxLayout.Y_AXIS)); JPanel panel = new JPanel(); contentPane.add(panel); panel.setLayout(null); JLabel lblNewLabel = new JLabel("请输入要查找的学生的学号:"); lblNewLabel.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel.setBounds(71, 0, 208, 29); panel.add(lblNewLabel); JLabel lblNewLabel_1 = new JLabel("学号:"); lblNewLabel_1.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1.setBounds(71, 105, 50, 30); panel.add(lblNewLabel_1); idField = new JTextField(); idField.setEditable(false); idField.setBounds(143, 99, 240, 45); panel.add(idField); idField.setColumns(10); JLabel lblNewLabel_1_1 = new JLabel("姓名:"); lblNewLabel_1_1.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1_1.setBounds(71, 160, 50, 30); panel.add(lblNewLabel_1_1); nameField = new JTextField(); nameField.setColumns(10); nameField.setBounds(143, 154, 240, 45); panel.add(nameField); JLabel lblNewLabel_1_1_1 = new JLabel("性别:"); lblNewLabel_1_1_1.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1_1_1.setBounds(71, 215, 50, 30); panel.add(lblNewLabel_1_1_1); genderField = new JTextField(); genderField.setColumns(10); genderField.setBounds(143, 209, 240, 45); panel.add(genderField); JLabel lblNewLabel_1_1_1_1 = new JLabel("出生日期:"); lblNewLabel_1_1_1_1.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1_1_1_1.setBounds(41, 270, 80, 30); panel.add(lblNewLabel_1_1_1_1); dobField = new JTextField(); dobField.setColumns(10); dobField.setBounds(143, 264, 240, 45); panel.add(dobField); JLabel lblNewLabel_1_1_1_2 = new JLabel("班级:"); lblNewLabel_1_1_1_2.setFont(new Font("宋体", Font.PLAIN, 16)); lblNewLabel_1_1_1_2.setBounds(71, 325, 50, 30); panel.add(lblNewLabel_1_1_1_2); batchField = new JTextField(); batchField.setColumns(10); batchField.setBounds(143, 319, 240, 45); panel.add(batchField); searchField = new JTextField(); searchField.setBounds(71, 39, 208, 45); panel.add(searchField); searchField.setColumns(10); JButton searchButton = new JButton("查找"); searchButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent arg0) { // 1.读出要查询的学生输入的id // 因为学生的学号是唯一的,所以我们根据学号查询后,只会有一条数据 // 转化一下数据类型 int id = Integer.parseInt(searchField.getText()); // 2.执行JDBC语句 try { SQLHelp sqlHelp = new SQLHelp(); Student student = sqlHelp.queryStudent(id); // 3.将查询结果填到文本框中 // 前提是学生存在 if(student != null) { idField.setText(String.valueOf(id)); nameField.setText(student.getName()); genderField.setText(student.getGender()); dobField.setText(student.getDob()); batchField.setText(String.valueOf(student.getBatch())); } else { // 此时学生不存在,提示用户,不存在该学生 JOptionPane.showMessageDialog(QueryFrame.this, "无此学生"); } } catch (SQLException e) { e.printStackTrace(); } } }); searchButton.setFont(new Font("宋体", Font.PLAIN, 18)); searchButton.setBounds(289, 42, 97, 39); panel.add(searchButton); } }
SQLHelp 工具类
package studentsmanager; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; public class SQLHelp { public static final String JDBC_DRIVER = "com.mysql.cj.jdbc.Driver"; public static final String DB_URL = "jdbc:mysql://localhost:3306/niit?useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=UTC"; public static final String username = "root"; public static final String password = "011216"; private Connection connection = null; private PreparedStatement pStatement = null; private ResultSet rSet = null; // 加载驱动 // 静态初始化块(只执行一次) static { try { Class.forName(JDBC_DRIVER); } catch (ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } } // 链接数据库 public void connectDB() { try { connection = DriverManager.getConnection(DB_URL,username,password); System.out.println("数据库链接成功"); } catch (SQLException e) { System.out.println("数据库链接失败"); e.printStackTrace(); } } // 关闭资源 public void close() { if(rSet != null) { try { rSet.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } if(pStatement != null) { try { pStatement.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } if(connection != null) { try { connection.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } public void addStudent(int id, String nameString, String genderString, String dobString, int batch) throws SQLException { // try finally 无论是否抛出异常都将执行 finally 中的语句 try { // 先链接到数据库 connectDB(); // sql 语句 // 静态 sql 语句需要进行字符串拼接 // 动态 sql 语句 String addsql = "insert into student values(?, ?, ?, ?, ?)"; pStatement = connection.prepareStatement(addsql); pStatement.setInt(1, id); pStatement.setString(2, nameString); pStatement.setString(3, genderString); pStatement.setString(4, dobString); pStatement.setInt(5, batch); pStatement.executeUpdate(); } finally { close(); } } public void changeStudent(int id, String nameString, String genderString, String dobString, int batch) throws SQLException { try { connectDB(); String changesql = "update student set name = ?, gender = ?, dob = ?, batch = ? where id = ?"; pStatement = connection.prepareStatement(changesql); pStatement.setString(1, nameString); pStatement.setString(2, genderString); pStatement.setString(3, dobString); pStatement.setInt(4, batch); pStatement.setInt(5, id); pStatement.executeUpdate(); } finally { close(); } } public void deletestudent(int id) throws SQLException { try { connectDB(); String deleteString = "select * from student where id = ?"; pStatement = connection.prepareStatement(deleteString); pStatement.setInt(1, id); pStatement.execute(); } finally { close(); } } public Student queryStudent(int id) throws SQLException { try { connectDB(); String querysql = "select * from student where id = ?"; pStatement = connection.prepareStatement(querysql); pStatement.setInt(1, id); // 三种方法执行 // execute() 都可以使用,返回true或false // executeQuery() 专门用于查询,返回结果集 // executeUpdate() 专门用于删除、更新 rSet = pStatement.executeQuery(); if(rSet.next()) { String nameString = rSet.getString(2); String genderString = rSet.getString(3); String dobString = rSet.getString(4); int batchString = rSet.getInt(5); // 查询到学生信息返回结果集 return new Student(nameString, genderString, dobString, batchString); } else { // 没有查询到学生信息,返回null return null; } } finally { close(); } } }
Student 工具类
package studentsmanager; public class Student { private String name; private String gender; private String dob; private int batch; public Student(String name, String gender, String dob, int batch) { this.name = name; this.gender = gender; this.dob = dob; this.batch = batch; } public String getName() { return name; } public String getGender() { return gender; } public String getDob() { return dob; } public int getBatch() { return batch; } }
这算一个比较完整的项目了,既有 GUI 又有 MySQL 数据库的已经 Java 的 JDBC ,虽然已经有了 GUI 界面,但很明显,没有进行任何美化,就只是简单的一个界面,勉勉强强可以看的过去,使用 JDBC 链接数据库的时候,没有实现可以直接在程序创建数据库,只能从数据库方创建数据库,这是一个缺点,同时使用 JDBC 链接数据库的时候,所使用的代码依旧是 MySQL 数据库的代码,(我 MySQL 学的不好,增删改查啥的数据库代码都还记不清楚 哭了…)还有就是当程序在进行修改和删除的时候,修改失败和删除失败的时候,都是因为数据链接失败了才进行弹窗,不知道怎么改成无法修改或者无法删除的时候提示,(又哭了…)
欢迎个位大佬指出错误,同时也欢迎各位小白借鉴,有问题的话,评论或者私聊都是可以的,看了就会回复!