java学生选课系统.docx

1、java学生选课系统需求分析：写一个较为严谨的学生选课系统，实现学生可以选择多门选课课程，并将有效选课结果保存到数据库。学生需要登录后，才能选课。让学生可以在选课系统通过多种方式查询到要选的课程信息。/选课规则：1、每个学生可以选多门课程，多次选课的总学分不能超过6学分；2、不能重复选择一门课程；3、每一门课程的选课人数都有数量限制，当某门课程的选课名额满时，则应另选课程。4、凭用户名和密码登录，通过提交某一课程号来选课/总体设计方案：建立三个类：登录类register，选课类studentChooseCourse,数据库工具类JDBCUtil；一个SQL脚本文件用于生成数据库表结构和初始记录

2、，以搭建数据库环境。登录类register类，负责对用户的身份进行验证；工具类JDBCUtil用于实现连接，你可调用JDBCUtil的getConnection()方法等到链接。选课类studentChooseCourse用于，实现选课功能。其中包括几个主要方法：1、actionPerformed(ActionEvent) 用于监听用户“查询”和“提交”操作，并负责调用各种方法对其进行处理2、createSearchCourse()用于产生图形用户界面3、processBeforeCommit()用于对用户的“提交”查找进行验证，剔除无效的用户操作4、tryCommit()负责对有效的“提交”

3、操作，进一步处理，并将有效的操作结果时时保存到数据库，并更新数据库原有信息/本程序用到的知识点：数据库连接JDBC；SQL建表、插入输入、动态查询；图形用户界面的产生以及处理查询结果集并较好显示；程序设计基础知识。 /代码如下：import java.awt.GridLayout;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.sql.*;import javax.swing.*;import javax.swing.table.DefaultTableModel;import

4、 school.schoolPicture.JdbcUtil;public class StudentChooseCourse extends JFrame implements ActionListener JTextField jtfSearch = new JTextField(11);String columnNames = new String 课程ID, 课程名, 学时, 学分, 学期, 性质 ;DefaultTableModel dtmSearch = new DefaultTableModel(columnNames, 27);JTable jtSearch = new JTa

5、ble(dtmSearch);JScrollPane jspSearch = new JScrollPane(jtSearch);JComboBox jcbSearch = new JComboBox();JTextField jtfSelectedCourse = new JTextField(10);Connection con = null;PreparedStatement ps = null;ResultSet rs = null;private static String usrName;private static String passwrd;public StudentCho

6、oseCourse(String usrName, String passwrd) createSearchCourse();this.usrName = usrName;this.passwrd = passwrd;public String getUsrName() return usrName;public void setUsrName(String usrName) this.usrName = usrName;public String getPasswrd() return passwrd;public void setPasswrd(String passwrd) this.p

7、asswrd = passwrd; public void actionPerformed(ActionEvent e) String str = e.getActionCommand();if (查询.trim().equals(str) int k = 1;while (k 10) for (int i = 1; i 7; i+) jtSearch.setValueAt(null, k - 1, i - 1);k+;searchAvailableCourse(); else if (提交.equals(str) boolean effect=processBeforeCommit(); i

8、f(effect=true)tryCommit();public boolean processBeforeCommit()int k = 1;while (k 10) for (int i = 1; i 6) JOptionPane.showMessageDialog(null, 你已经选满6学分，系统将退出);this.setVisible(false);return false;sql = select * from choicesxx where sname=? and cno=?;boolean flag = false;try ps = con.prepareStatement(s

9、ql);ps.setString(1, this.getUsrName();ps.setString(2, userInput);rs = ps.executeQuery();flag = rs.next(); catch (Exception eaa) eaa.printStackTrace();if (flag) JOptionPane.showMessageDialog(null, 你已经选择了该课程。请另选课程);return false;return true;public void tryCommit() String userInput = jtfSelectedCourse.g

10、etText().toString().trim().toLowerCase();PreparedStatement ps;String sql = select (Max-selectedCount) as RemainedCount + from Coursexx where cno=?;try ps = con.prepareStatement(sql);ps.setString(1, userInput);rs = ps.executeQuery();ResultSetMetaData meta = rs.getMetaData();int cols = meta.getColumnC

11、ount();int RemainedCount = -1;while (rs.next() RemainedCount = rs.getInt(1);System.out.println(RemainedCount: + RemainedCount);if (RemainedCount 0) sql = insert into choicesxx values(?,?);ps = con.prepareStatement(sql);ps.setString(1, this.getUsrName();ps.setString(2, userInput);ps.executeUpdate();J

12、OptionPane.showMessageDialog(null, 选课成功： + this.getUsrName()+ 选了 + userInput + . + + 还有 + RemainedCount+ 人可以选该课程。);sql = update CourseXX set selectedCount=selectedCount+1 where cno=?;ps = con.prepareStatement(sql);ps.setString(1, userInput);ps.executeUpdate();mit(); catch (Exception es) es.printStac

13、kTrace();try con.rollback(); catch (Exception ey) ey.printStackTrace();public void searchAvailableCourse() if (JDBCUtil.getConnection() != null) System.out.println(JDBCUtil.getConnection();con = JDBCUtil.getConnection(); else con = JdbcUtil.getConnection();String userInput = jtfSearch.getText().toSt

14、ring().trim().toLowerCase();String selectedItem = jcbSearch.getSelectedItem().toString().trim();System.out.println(User search: + userInput);System.out.println(selectedItem: + selectedItem);String sql = null;try if (课程名.equals(selectedItem) sql = select cno,cname,hour,grade,term,isNeed from CourseXX

15、 where cname = ?;ps = con.prepareStatement(sql);ps.setString(1, userInput); else if (课程ID.equals(selectedItem) sql = select cno,cname,hour,grade,term,isNeed from CourseXX where cno = ?;ps = con.prepareStatement(sql);ps.setString(1, userInput); else if (学时.equals(selectedItem) sql = select cno,cname,

16、hour,grade,term,isNeed from CourseXX where hour = ?;ps = con.prepareStatement(sql);ps.setInt(1, Integer.parseInt(userInput); else if (学分.equals(selectedItem) sql = select cno,cname,hour,grade,term,isNeed from CourseXX where grade = ?;ps = con.prepareStatement(sql);ps.setInt(1, Integer.parseInt(userI

17、nput); else if (学期.equals(selectedItem) sql = select cno,cname,hour,grade,term,isNeed from CourseXX where term = ?;ps = con.prepareStatement(sql);ps.setString(1, userInput);System.out.println(sql);rs = ps.executeQuery();mit();ResultSetMetaData meta = rs.getMetaData();int cols = meta.getColumnCount()

18、;String result = null;int k = 1;boolean flag = false;while (rs.next() for (int i = 1; i = cols; i+) result = rs.getString(i);System.out.println(result);jtSearch.setValueAt(result, k - 1, i - 1);k+;flag = true;if (flag = false) JOptionPane.showMessageDialog(null, 该课程不存在，请重新输入);return; catch (Exceptio

19、n ex) ex.printStackTrace();try con.rollback(); catch (Exception er) er.printStackTrace();public void createSearchCourse() this.setLayout(new GridLayout(3, 1);JPanel jp1 = new JPanel();jp1.setLayout(new GridLayout(4, 1);JPanel jp2 = new JPanel();JPanel jp3 = new JPanel();JPanel jp10 = new JPanel();JP

20、anel jp11 = new JPanel();JPanel jp12 = new JPanel();JPanel jp13 = new JPanel();JLabel jlSearch = new JLabel( 学 生 选 课 系 统 );jp11.add(jlSearch);jcbSearch.addItem(new String(课程名);jcbSearch.addItem(new String(课程ID);jcbSearch.addItem(new String(学时);jcbSearch.addItem(new String(学分);jcbSearch.addItem(new S

21、tring(学期);jp12.add(jtfSearch);jp12.add(jcbSearch);JButton jbOK = new JButton(查询);jbOK.addActionListener(this);jbOK.setSize(90, 20);jp13.add(jbOK);jp1.add(jp10);jp1.add(jp11);jp1.add(jp12);jp1.add(jp13);jp2.add(jspSearch);JLabel jlSelectedCourse = new JLabel(请输入课程ID：);JButton jbSelectedCourse = new J

22、Button(提交);jbSelectedCourse.addActionListener(this);jp3.add(jlSelectedCourse);jp3.add(jtfSelectedCourse);jp3.add(jbSelectedCourse);this.add(jp1);this.add(jp2);this.add(jp3);this.setVisible(true);this.setSize(485, 600);public static void main(String args) /String usrName = xuliang;/String passwrd = 1

23、23;new StudentChooseCourse(usrName, passwrd);drop table registerXu;create table registerXu (id varchar(20),userName varchar(20),passWord varchar(20),identify varchar(20);insert into registerXu values(s001,xuliang,123,学生);insert into registerXu values(s002,xuliang2,1234,学生);insert into registerXu val

24、ues(j001,jack,12345,学生);insert into registerXu values(001,user,user,学生);insert into registerXu values(z001,zlm,corejava,老师);String sql = select * from registerXu + where userName=? and passWord=? and identify=?;/table 2:Coursexx课程表drop table Coursexx;create table Coursexx(cno varchar(20) primary key

25、,cname varchar(20),hour Int,grade Int,term varchar(20),isNeed varchar(20), selectedCount Int ,Max Int);insert into Coursexx values(c001,CoreJava,50,5,201007,NoNecessary,0,50);insert into Coursexx values(c002,XML,20,2,201008,NoNecessary,0,40);insert into Coursexx values(c003,HIBERNATE,20,4,201008,NoN

26、ecessary,0,30);insert into Coursexx values(c004,SQL,20,4,201006,NoNecessary,0,5);insert into Coursexx values(c005,JDBC,20,2,201008,NoNecessary,0,3);insert into Coursexx values(c006,AJAX,20,2,201010,NoNecessary,0,1);insert into Coursexx values(c007,JSP,100,8,201009,NoNecessary,0,1sql = select cno,cname,hour,grade,term,isNeed from CourseXX where cname = ?; /table 3:学生表-drop table studentxx;create table studentxx(sid varchar(20),sname varchar(20) primary key,sex varchar(20),birthday varchar(20),className varchar(20), image varchar(20);insert into studentxx values(s001,xuliang