基于Java+MySQL的学生选课系统，Eclipse完美运行，满分数据库课程设计，新手必看！

package data; import javax.swing.*; import javax.swing.table.DefaultTableModel; import java.awt.*; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.ItemEvent; import java.awt.event.ItemListener; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.Vector; public class couse_result extends Panel implements ActionListener { // 定义组件 JLabel jLStudentInfoTable = null;//学生信息表 JLabel jLSelectQueryField = null;//选择查询字段 JLabel jLEqual = null;//= JLabel jLsno = null;//学号 JLabel jLsname = null;//姓名 JLabel jLcno = null;//性别 JLabel jLcname = null;//年龄 JLabel jLcoom = null;//专业 JLabel jLteme = null;//住址 JLabel jLcji = null;//住址 JLabel jLtea = null;//住址 JTextField jTFQueryField = null;//查询字段 JTextField jTFsno = null;//学号 JTextField jTFsname = null;//姓名 JTextField jTFcno = null;//性别 JTextField jTFcname = null;//年龄 JTextField jTFcoom = null;//专业 JTextField jTFtime = null;//住址 JTextField jTFcji = null;//住址 JTextField jTFtea = null;//住址 JButton jBQuery = null;//查询 JButton jBQueryAll = null;//查询所有记录 JButton jBInsert = null;//插入 JButton jBUpdate = null;//更新 JButton jBDeleteCurrentRecord = null;//删除当前记录 JButton jBDeleteAllRecords = null;//删除所有记录 //JComboBox jCBSelectQueryField = null; JComboBox<String> jCBSelectQueryField = null;//查询字段 JPanel jP1, jP2,jP3,jP4,jP5,jP6,jP7 = null; JPanel jPTop, jPBottom = null; DefaultTableModel studentTableModel = null; JTable studentJTable = null; JScrollPane studentJScrollPane = null; Vector studentVector = null; Vector titleVector = null; private static DbProcess dbProcess; String SelectQueryFieldStr = "学号"; // 构造函数 public couse_result() { // 创建组件 jLStudentInfoTable = new JLabel("选课结果"); jLSelectQueryField = new JLabel("选择查询字段"); jLEqual = new JLabel(" = "); jLsno = new JLabel("学 号 "); jLsname = new JLabel(" 姓 名 "); jLcno = new JLabel(" 课程号 "); jLcname = new JLabel("课程名"); jLcoom = new JLabel("上课教室"); jLteme = new JLabel("上课时间"); jLcji = new JLabel("课程学分"); jLtea = new JLabel("任课教师"); jTFQueryField = new JTextField(18);//查询字段 jTFsno = new JTextField(14);//学号 jTFsname = new JTextField(14);//姓名 jTFcno = new JTextField(14);//性别 jTFcname = new JTextField(14);//年龄 jTFcoom = new JTextField(14);//专业 jTFtime = new JTextField(14);//住址 jTFcji = new JTextField(14);//住址 jTFtea = new JTextField(14);//住址 jBQuery = new JButton("查询选课结果"); jBQueryAll = new JButton("查询所有记录"); jBInsert = new JButton("插入选课"); jBUpdate = new JButton("修改选课"); jBDeleteCurrentRecord = new JButton("删除当前记录"); jBDeleteAllRecords = new JButton("删除所有记录"); // 设置监听 jBQuery.addActionListener(this); jBQueryAll.addActionListener(this); jBInsert.addActionListener(this); jBUpdate.addActionListener(this); jBDeleteCurrentRecord.addActionListener(this); jBDeleteAllRecords.addActionListener(this); jCBSelectQueryField = new JComboBox<String>();//查询字段 jCBSelectQueryField.addItem("学号"); jCBSelectQueryField.addItem("姓名"); jCBSelectQueryField.addItem("课程号"); jCBSelectQueryField.addItem("课程名"); jCBSelectQueryField.addItem("上课教室"); jCBSelectQueryField.addItem("上课时间"); jCBSelectQueryField.addItem("课程学分"); jCBSelectQueryField.addItem("任课教师"); jCBSelectQueryField.addItemListener(new ItemListener() {//下拉框事件监听 public void itemStateChanged(ItemEvent event) { switch (event.getStateChange()) { case ItemEvent.SELECTED: SelectQueryFieldStr = (String) event.getItem(); System.out.println("选中：" + SelectQueryFieldStr); break; case ItemEvent.DESELECTED: System.out.println("取消选中：" + event.getItem()); break; } } }); studentVector = new Vector(); titleVector = new Vector(); // 定义表头 titleVector.add("学 号"); titleVector.add("姓 名"); titleVector.add("课程号"); titleVector.add("课程名"); titleVector.add("上课教室"); titleVector.add("上课时间"); titleVector.add("课程学分"); titleVector.add("任课教师"); //studentTableModel = new DefaultTableModel(tableTitle, 15); studentJTable = new JTable(studentVector, titleVector); studentJTable.setPreferredScrollableViewportSize(new Dimension(600,200)); studentJScrollPane = new JScrollPane(studentJTable); //分别设置水平和垂直滚动条自动出现 studentJScrollPane.setHorizontalScrollBarPolicy( JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED); studentJScrollPane.setVerticalScrollBarPolicy( JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED); //为表格添加监听器 studentJTable.addMouseListener(new MouseAdapter() { public void mouseClicked(MouseEvent e) { int row = ((JTable) e.getSource()).rowAtPoint(e.getPoint()); // 获得行位置 System.out.println("mouseClicked(). row = " + row); Vector v = new Vector(); v = (Vector) studentVector.get(row); jTFsno.setText((String) v.get(0));// 学号 jTFsname.setText((String) v.get(1));// 姓名 jTFcno.setText((String) v.get(2));// 性别 jTFcname.setText((String) v.get(3));// 年龄 jTFcoom.setText((String) v.get(4));// 专业 jTFtime.setText((String) v.get(5));// 住址 jTFcji.setText((String) v.get(6));// 住址 jTFtea.setText((String) v.get(7));// 住址 } }); jP1 = new JPanel(); jP2 = new JPanel(); jP3 = new JPanel(); jP4 = new JPanel(); jP5 = new JPanel(); jP6 = new JPanel(); jP7 = new JPanel(); jPTop = new JPanel(); jPBottom = new JPanel(); jP1.add(jLStudentInfoTable,BorderLayout.SOUTH); jP2.add(studentJScrollPane); jP3.add(jLSelectQueryField); jP3.add(jCBSelectQueryField); jP3.add(jLEqual); jP3.add(jTFQueryField); jP3.add(jBQuery); jP3.add(jBQueryAll); jP3.setLayout(new FlowLayout(FlowLayout.LEFT)); jP3.setPreferredSize(new Dimension(20,20)); jP4.add(jLsno); jP4.add(jTFsno); jP4.add(jLsname); jP4.add(jTFsname); jP4.add(jLcno); jP4.add(jTFcno); jP4.setLayout(new FlowLayout(FlowLayout.CENTER)); jP4.setPreferredSize(new Dimension(20,20)); jP5.add(jLcname); jP5.add(jTFcname); jP5.add(jLcoom); jP5.add(jTFcoom); jP5.add(jLteme); jP5.add(jTFtime); jP5.setLayout(new FlowLayout(FlowLayout.CENTER)); jP5.setPreferredSize(new Dimension(20,20)); jP6.add(jLcji); jP6.add(jTFcji); jP6.add(jLtea); jP6.add(jTFtea); jP6.setLayout(new FlowLayout(FlowLayout.CENTER)); jP6.setPreferredSize(new Dimension(20,20)); jP7.add(jBInsert); jP7.add(jBUpdate); jP7.add(jBDeleteCurrentRecord); jP7.add(jBDeleteAllRecords); jP7.setLayout(new FlowLayout(FlowLayout.CENTER)); jP7.setPreferredSize(new Dimension(20,20)); jPTop.add(jP1); jPTop.add(jP2); jPBottom.setLayout(new GridLayout(5, 1)); jPBottom.add(jP3); jPBottom.add(jP4); jPBottom.add(jP5); jPBottom.add(jP6); jPBottom.add(jP7); this.add("North", jPTop); this.add("South", jPBottom); this.setLayout(new GridLayout(2, 1)); //this.setTitle(""); this.setSize(700, 652); this.setLocation(150, 150); //this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); this.setVisible(true); //this.setResizable(false); dbProcess = new DbProcess(); } @Override public void actionPerformed(ActionEvent e) { if(e.getActionCommand().equals("查询选课结果") && !jTFQueryField.getText().isEmpty()){ System.out.println("actionPerformed(). 查询"); String sQueryField = jTFQueryField.getText().trim(); queryProcess(sQu