于鸿硕面向对象设计大作业02
面向对象设计大作业02
网安2411 于鸿硕 202421336018
一、改造思路
1.MVC模式
MVC模式 即Model-View-Controller（模型-视图-控制器）模式，通过分三种实现模块进行；对于本项目，设计MVC模式如下
graph TD
M[Model]-->|数据存储|S[Student.java]-->StudentController.java
M-->|业务方法|StudentManagementSystem.java-->StudentController.java
View-->|控制台视图|ConsoleView.java-->StudentController.java
View-->|用户图形视图|GUIView.java-->StudentController.java
StudentController.java-->Controller
总体上，通过StudentController对Model和View进行调动，实现程序运行
2.GUI实现
使用JTable表格的方式展示学生数据，实现数据直接可视化
3.双界面支持
程序启动时选择使用的界面类型，两种界面指向共同的控制器和模型以精简代码和减小时空复杂度，两种界面数据和功能互通
二、实现方式
1.Model
model模块Student和StudentManagementSystem两个类沿用既有类，不作修改
2.View
StudentView.java（视图接口类）
用该类承接Main方法引入的视图，并初始化视图方法
package code;
import java.util.List;
public interface StudentView {
void setController(StudentController controller);
void updateStudentList(List<Student> students);
void showSearchResults(List<Student> results);
void showMessage(String message);
void start();
}
ConsoleView.java（控制台视图）
该类可直接继承原系统中Main文件的代码，通过Override实现该类方法
package code;
import java.util.List;
import java.util.Scanner;
public class ConsoleView implements StudentView {
private StudentController controller;
private Scanner scanner;
public ConsoleView() {
scanner = new Scanner(System.in);
}
@Override
public void setController(StudentController controller) {
this.controller = controller;
}
@Override
public void updateStudentList(List<Student> students) {
if (students.isEmpty()) {
System.out.println("系统中没有学生数据!");
return;
}
System.out.println("学生列表:");
for (Student student : students) {
System.out.println(student);
}
}
@Override
public void showSearchResults(List<Student> results) {
if (results.isEmpty()) {
System.out.println("没有找到匹配的学生!");
} else {
System.out.println("搜索结果:");
for (Student student : results) {
System.out.println(student);
}
}
}
@Override
public void showMessage(String message) {
System.out.println(message);
}
@Override
public void start() {
boolean running = true;
while (running) {
System.out.println("\n===== 学生管理系统 =====");
System.out.println("1. 添加学生");
System.out.println("2. 移除学生");
System.out.println("3. 按姓名搜索");
System.out.println("4. 按专业搜索");
System.out.println("5. 按GPA搜索");
System.out.println("6. 显示所有学生");
System.out.println("7. 退出");
System.out.print("请选择操作: ");
int choice = scanner.nextInt();
scanner.nextLine(); // consume newline
switch (choice) {
case 1:
addStudentForm();
break;
case 2:
removeStudentForm();
break;
case 3:
searchByNameForm();
break;
case 4:
searchByMajorForm();
break;
case 5:
searchByGpaForm();
break;
case 6:
controller.showAllStudents();
break;
case 7:
running = false;
System.out.println("系统已退出");
break;
default:
System.out.println("无效的选择，请重试");
}
}
scanner.close();
}
private void addStudentForm() {
System.out.print("请输入学生姓名: ");
String name = scanner.nextLine();
System.out.print("请输入学生年龄: ");
int age = scanner.nextInt();
scanner.nextLine();
System.out.print("请输入学生性别: ");
String gender = scanner.nextLine();
System.out.print("请输入学生ID: ");
String id = scanner.nextLine();
System.out.print("请输入学生专业: ");
String major = scanner.nextLine();
System.out.print("请输入学生GPA: ");
double gpa = scanner.nextDouble();
controller.addStudent(name, age, gender, id, major, gpa);
showMessage("学生添加成功!");
}
private void removeStudentForm() {
System.out.print("请输入要移除的学生ID: ");
String id = scanner.nextLine();
boolean removed = controller.removeStudent(id);
if (removed) {
showMessage("学生移除成功!");
} else {
showMessage("未找到该学生!");
}
}
private void searchByNameForm() {
System.out.print("请输入要搜索的学生姓名: ");
String name = scanner.nextLine();
controller.searchByName(name);
}
private void searchByMajorForm() {
System.out.print("请输入要搜索的专业: ");
String major = scanner.nextLine();
controller.searchByMajor(major);
}
private void searchByGpaForm() {
System.out.print("请输入要搜索的GPA: ");
double gpa = scanner.nextDouble();
controller.searchByGpa(gpa);
}
}
GUIView.java（图形视图）
通过Swing GUI展示用户界面，通过JButton、JField创建交互，新建或Override方法对接Controller
// GUIView.java (GUI视图)
package code;
import javax.swing.*;
import javax.swing.table.DefaultTableModel;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.List;
public class GUIView extends JFrame implements StudentView {
private StudentController controller;
private DefaultTableModel tableModel;
private JTable table;
private JTextField nameField, ageField, genderField, idField, majorField, gpaField;
private JTextField searchField;
public GUIView() {
setTitle("学生管理系统");
setSize(800, 600);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(new BorderLayout());
initComponents();
setLocationRelativeTo(null);
}
private void initComponents() {
// 表格设置
String[] columns = {"姓名", "年龄", "性别", "ID", "专业", "GPA"};
tableModel = new DefaultTableModel(columns, 0);
table = new JTable(tableModel);
add(new JScrollPane(table), BorderLayout.CENTER);
// 控制面板
JPanel controlPanel = new JPanel(new GridLayout(3, 1));
// 添加学生面板
JPanel addPanel = new JPanel(new FlowLayout());
addPanel.setBorder(BorderFactory.createTitledBorder("添加学生"));
addPanel.add(new JLabel("姓名:"));
nameField = new JTextField(5);
addPanel.add(nameField);
addPanel.add(new JLabel("年龄:"));
ageField = new JTextField(3);
addPanel.add(ageField);
addPanel.add(new JLabel("性别:"));
genderField = new JTextField(3);
addPanel.add(genderField);
addPanel.add(new JLabel("ID:"));
idField = new JTextField(5);
addPanel.add(idField);
addPanel.add(new JLabel("专业:"));
majorField = new JTextField(8);
addPanel.add(majorField);
addPanel.add(new JLabel("GPA:"));
gpaField = new JTextField(3);
addPanel.add(gpaField);
JButton addButton = new JButton("添加");
addButton.addActionListener(e -> addStudentAction());
addPanel.add(addButton);
controlPanel.add(addPanel);
// 搜索面板
JPanel searchPanel = new JPanel(new FlowLayout());
searchPanel.setBorder(BorderFactory.createTitledBorder("搜索学生"));
searchField = new JTextField(10);
searchPanel.add(searchField);
JButton nameSearchButton = new JButton("按姓名搜索");
nameSearchButton.addActionListener(e -> searchByNameAction());
searchPanel.add(nameSearchButton);
JButton majorSearchButton = new JButton("按专业搜索");
majorSearchButton.addActionListener(e -> searchByMajorAction());
searchPanel.add(majorSearchButton);
JButton gpaSearchButton = new JButton("按GPA搜索");
gpaSearchButton.addActionListener(e -> searchByGpaAction());
searchPanel.add(gpaSearchButton);
controlPanel.add(searchPanel);
// 操作面板
JPanel actionPanel = new JPanel(new FlowLayout());
JButton removeButton = new JButton("移除选中学生");
removeButton.addActionListener(e -> removeStudentAction());
actionPanel.add(removeButton);
JButton showAllButton = new JButton("显示所有学生");
showAllButton.addActionListener(e -> controller.showAllStudents());
actionPanel.add(showAllButton);
JButton exitButton = new JButton("退出");
exitButton.addActionListener(e -> System.exit(0));
actionPanel.add(exitButton);
controlPanel.add(actionPanel);
add(controlPanel, BorderLayout.NORTH);
}
private void addStudentAction() {
try {
String name = nameField.getText();
int age = Integer.parseInt(ageField.getText());
String gender = genderField.getText();
String id = idField.getText();
String major = majorField.getText();
double gpa = Double.parseDouble(gpaField.getText());
controller.addStudent(name, age, gender, id, major, gpa);
// 清空输入框
nameField.setText("");
ageField.setText("");
genderField.setText("");
idField.setText("");
majorField.setText("");
gpaField.setText("");
showMessage("学生添加成功");
} catch (NumberFormatException ex) {
showMessage("输入格式错误，请检查年龄和GPA是否为数字");
}
}
private void removeStudentAction() {
int selectedRow = table.getSelectedRow();
if (selectedRow >= 0) {
String id = (String) tableModel.getValueAt(selectedRow, 3);
boolean removed = controller.removeStudent(id);
if (removed) {
showMessage("学生移除成功");
} else {
showMessage("学生移除失败");
}
} else {
showMessage("请先选择要移除的学生");
}
}
private void searchByNameAction() {
String name = searchField.getText();
controller.searchByName(name);
}
private void searchByMajorAction() {
String major = searchField.getText();
controller.searchByMajor(major);
}
private void searchByGpaAction() {
try {
double gpa = Double.parseDouble(searchField.getText());
controller.searchByGpa(gpa);
} catch (NumberFormatException ex) {
showMessage("GPA必须是数字");
}
}
@Override
public void setController(StudentController controller) {
this.controller = controller;
}
@Override
public void updateStudentList(List<Student> students) {
tableModel.setRowCount(0); // 清空表格
for (Student student : students) {
Object[] row = {
student.getName(),
student.getAge(),
student.getGender(),
student.getId(),
student.getMajor(),
student.getGpa()
};
tableModel.addRow(row);
}
}
@Override
public void showSearchResults(List<Student> results) {
updateStudentList(results);
showMessage("找到 " + results.size() + " 个匹配结果");
}
@Override
public void showMessage(String message) {
JOptionPane.showMessageDialog(this, message);
}
@Override
public void start() {
setVisible(true);
}
}
3.Controller
StudentController.java（控制器）
作为视图和模型的中继器，实现Student的getter、setter方法
package code;
import java.util.List;
public class StudentController {
private StudentManagementSystem model;
private StudentView view;
public StudentController(StudentManagementSystem model, StudentView view) {
this.model = model;
this.view = view;
this.view.setController(this);
}
// 添加学生
public void addStudent(String name, int age, String gender, String id, String major, double gpa) {
Student student = new Student(name, age, gender, id, major, gpa);
model.addStudent(student);
view.updateStudentList(model.getStudents());
}
// 移除学生
public boolean removeStudent(String id) {
Student student = model.getStudentById(id);
if (student != null) {
model.removeStudent(student);
view.updateStudentList(model.getStudents());
return true;
}
return false;
}
// 按姓名搜索
public void searchByName(String name) {
List<Student> results = model.searchByName(name);
view.showSearchResults(results);
}
// 按专业搜索
public void searchByMajor(String major) {
List<Student> results = model.searchByMajor(major);
view.showSearchResults(results);
}
// 按GPA搜索
public void searchByGpa(double gpa) {
List<Student> results = model.searchByGpa(gpa);
view.showSearchResults(results);
}
// 显示所有学生
public void showAllStudents() {
view.updateStudentList(model.getStudents());
}
}
4.Main.java
对Main方法进行重新设计，进入程序后先映入界面选择，而后通过View类进入对应的界面，再而创建控制器关联模型和视图，最后启动程序
package code;
import javax.swing.*;
public class Main {
public static void main(String[] args) {
StudentManagementSystem model = new StudentManagementSystem();
String[] options = {"控制台界面", "GUI界面"};
int choice = JOptionPane.showOptionDialog(
null,
"请选择界面类型",
"学生管理系统",
JOptionPane.DEFAULT_OPTION,
JOptionPane.INFORMATION_MESSAGE,
null,
options,
options[0]
);
StudentView view;
if (choice == 1) {
view = new GUIView();
} else {
view = new ConsoleView();
}
StudentController controller = new StudentController(model, view);
view.start();
}
}
三、运行截图
图1 界面分流
图2 控制台视图菜单栏
图3.1 GUI视图首页
图3.2 GUI添加学生
图3.3 GUI按专业搜索
图3.4 GUI按GPA搜索
图3.5 GUI显示所有学生
图3.6 GUI选中移除学生
四、总结说明
本次实验通过学习MVC模式、JTable展示模式概念和方法，将各个类框架及其要求输出给豆包AI，后得到完整代码。
代码中最大的难理解点是多态多接口情况下，容易被多个类和方法绕晕，不知道这段代码指给谁，只懂得代码起什么作用，不懂得其背后的逻辑；解决的好方法是建立精细的思维导图，精细到每个类的每个方法，在结构可视化后代码底层逻辑变得清晰好理解
代码一大复杂度出现在Swing GUI专属的类处，由于图形界面需要多条指令来实现单个方法，所以代码会堆积复杂，串联程度很高，对于程序员来说维护成本和难度也很高
综上，我发现MVC和GUI模式结合的这种方法好处体现在框架明确，在全局上连通性好、对某个方法修改不需要到每一个类里一个一个重新写，同时具有接入更多功能和更多模块的良好适应性，但是对于较小型的程序，例如这次改造的学生管理系统，会造成代码过多过繁杂，反向增加维护成本，瑜不掩瑕。
所以我认为，MVC模式适用于较大型、未来扩充可能大的系统，GUI图形适用于需要商品化、专业化、美观化的程序产品；如果是不需要完成以上需求的程序，例如较小型的、仅供程序员和技术人员监控、更改的专业小应用程序，使用传统的控制台模式更方便便捷。
在得出上述结论以外，我学习了GUI的语法和MVC模式思想，基本掌握了调用AI改造自己程序的方法。
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