ddelete3m3.setFontt private void addMenu2 //将菜单加入到菜单栏中 m2.addadd2m2.addupdata2m2.adddelete2m2.setFontt private void addMenu1 m1.addadd1m1.addupdata1m1.adddelete1m1.setFontt public void actionPerformedActionEvent e Object obje.getSource ifobjm5System.exit0 elseifobjadd1card.showpCenterquot增加学生界面quot elseifobjupdata1 card.showpCenterquot修改学生界面quot elseifobjdelete1 card.showpCenter quot删除学生界面quot elseifobjadd2 card.showpCenter quot增加课程界面quot elseifobjdelete2 card.showpCenter quot删除课程界面quot elseifobjupdata2 card.showpCenter quot修改课程界面quot elseifobjadd3 card.showpCenter quot增加选课界面quot elseifobjdelete3 card.showpCenter quot删除选课界面quot elseifobjupdata3 card.showpCenter quot修改选课界面quot elseifobj学生查询 card.showpCenter quot学生查询界面quot public static void mainString args new Menu效果图：添加界面:AddC.java/AddSC.java/Addstu.java添加数据时，若遇到必须信息未填写、不能重复的信息在数据库中已存在，都会提示无法添加及其错误原因。

    import java.awt.import javax.swing.import java.sql.import java.awt.event.public class AddC extends JPanel implements ActionListener JTextField 课号课名 JButton 录入public AddC tryUIManager.setLookAndFeelUIManager.getSystemLookAndFeelClassNamecatchException eSystem.err.printlnquot不能设置外观: quote 课号new JTextField12 课名new JTextField12 录入new JButtonquot录入quot 录入.addActionListenerthis Box box1Box.createHorizontalBox//横放box Box box2Box.createHorizontalBox Box box3Box.createHorizontalBox Box box4Box.createHorizontalBox box1.addnew JLabelquot课号:quot box1.add课号 box2.addnew JLabelquot课名:quot box2.add课名 box4.add录入 Box boxHBox.createVerticalBox//竖放box boxH.addbox1 boxH.addbox2 boxH.addbox3 boxH.addbox4 boxH.addBox.createVerticalGlue JPanel messPanelnew JPanel messPanel.addboxH setLayoutnew BorderLayout addmessPanelBorderLayout.CENTER validate效果图：添加界面:UpdateC.java/UpdateSC.java /Updatestu.java ，则会进行查询，如果修先查找你想要修改的项目，若修改的信息包括号码（学号、课号）改后的号码已存在，以及修改后必须的信息变成空都会提示无法修改和其错误原因。

    此外，若修改C表或则S表，会连同SC表中对应的信息一起修改。

    import java.awt.import java.awt.event.import java.sql.import javax.swing.public class UpdateC extends JPanel implements ActionListener String savenull JTextField 课号1课号课名 JButton 修改查找public UpdateC tryUIManager.setLookAndFeelUIManager.getSystemLookAndFeelClassNamecatchException eSystem.err.printlnquot不能设置外观: quote 课号1new JTextField12 课号new JTextField12 课名new JTextField12 修改new JButtonquot修改quot 查找new JButtonquot查找quot Box box1Box.createHorizontalBox//横放box Box box2Box.createHorizontalBox Box box3Box.createHorizontalBox Box box4Box.createHorizontalBox Box box5Box.createHorizontalBox box1.addnew JLabelquot课号:quotJLabel.CENTER box1.add课号 box2.addnew JLabelquot课名:quotJLabel.CENTER box2.add课名 box3.add修改 box5.addnew JLabelquot课号:quotJLabel.CENTER box5.add课号1 box5.add查找 修改.addActionListenerthis 查找.addActionListenerthis Box boxHBox.createVerticalBox//竖放box boxH.addbox1 boxH.addbox2 boxH.addbox3 boxH.addbox4 boxH.addBox.createVerticalGlue JPanel picPanelnew JPanel JPanel messPanelnew JPanel messPanel.addbox5 picPanel.addboxH setLayoutnew BorderLayout JSplitPane splitVnewJSplitPaneJSplitPane