JOptionPane需要的接口名字

JOptionPane是Java Swing库中的一个类，它提供了一些对话框的方法，用于与用户进行交互。如果你想在Java程序中使用JOptionPane，需要导入javax.swing包。在代码中，需要使用JOptionPane类的静态方法来创建对话框，例如：

import javax.swing.JOptionPane;

// 创建一个简单的信息框
JOptionPane.showMessageDialog(null, "Hello, world!");

// 创建一个带有OK和取消按钮的确认框
int result = JOptionPane.showConfirmDialog(null, "Are you sure?");
if (result == JOptionPane.OK_OPTION) {
    // 用户点击了OK按钮
} else {
    // 用户点击了取消按钮或关闭了对话框
}

// 创建一个带有文本框的输入框
String input = JOptionPane.showInputDialog(null, "Please enter your name:");
if (input != null) {
    // 用户输入了文本并点击了OK按钮
} else {
    // 用户点击了取消按钮或关闭了对话框
}

这里的接口名字指的是Java Swing库中用于显示对话框的接口，它并不是JOptionPane所需要的接口名字。

相关问题

用Java编写以下题目 1.编写一个算数测试小软件，用来训练小学生的算数能力。程序由3个类组成，其中Teacher对象充当监视器，负责给出算术题目，并判断回答者的答案是否正确；ComputerFrame对象负责为算术题目提供视图，比如用户可以通过ComputerFrame对象提供的GUI界面看到题目，并通过该GUI界面给出题目的答案；MailClass是软件的主类。 2.编写一个Book类，该类至少有price成员变量。该类要实现Comparable接口，在接口的compartTo（）方法中规定Book类的两个实例的大小关系为两者的price成员的大小关系。 编写一个主类SortSearchMainClass，在main()方法中将Book类的若干个对象存放在一个链表中，然后用Book类创建一个新的对象，并检查这个对象和链表中的哪些对象相等。 3.使用某种数据库管理系统，建立一个名字为Book的数据库，在数据库中建立bookList表，该表的字段为： ISBN（varchar），name(varchar),price(float),chubanDate(date) 其中ISBN为主键。 编程实现在bookList表中随机查询10条记录，并计算出这10条记录price字段值的平均值，即计算平均价格。

1. 算数测试小软件

Teacher类：

public class Teacher {
    private int num1;
    private int num2;
    private int answer;

    public void setQuestion() {
        num1 = (int) (Math.random() * 100);
        num2 = (int) (Math.random() * 100);
        answer = num1 + num2;
    }

    public boolean checkAnswer(int userAnswer) {
        return userAnswer == answer;
    }
}

ComputerFrame类：

import javax.swing.*;
import java.awt.*;

public class ComputerFrame extends JFrame {
    private JLabel questionLabel;
    private JTextField answerField;
    private JButton submitButton;
    private Teacher teacher;

    public ComputerFrame(Teacher teacher) {
        this.teacher = teacher;

        questionLabel = new JLabel();
        answerField = new JTextField();
        submitButton = new JButton("提交");

        Container container = getContentPane();
        container.setLayout(new FlowLayout());
        container.add(questionLabel);
        container.add(answerField);
        container.add(submitButton);

        setSize(300, 100);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setVisible(true);

        setQuestion();
        submitButton.addActionListener(event -> checkAnswer());
    }

    private void setQuestion() {
        teacher.setQuestion();
        questionLabel.setText(teacher.getNum1() + " + " + teacher.getNum2() + " = ");
    }

    private void checkAnswer() {
        int userAnswer = Integer.parseInt(answerField.getText());
        if (teacher.checkAnswer(userAnswer)) {
            JOptionPane.showMessageDialog(this, "回答正确！", "提示", JOptionPane.INFORMATION_MESSAGE);
        } else {
            JOptionPane.showMessageDialog(this, "回答错误！", "提示", JOptionPane.ERROR_MESSAGE);
        }
        setQuestion();
        answerField.setText("");
    }
}

MailClass类：

public class MainClass {
    public static void main(String[] args) {
        Teacher teacher = new Teacher();
        ComputerFrame computerFrame = new ComputerFrame(teacher);
    }
}

2. Book类

public class Book implements Comparable<Book> {
    private double price;

    public Book(double price) {
        this.price = price;
    }

    public double getPrice() {
        return price;
    }

    public void setPrice(double price) {
        this.price = price;
    }

    @Override
    public int compareTo(Book book) {
        if (this.price > book.price) {
            return 1;
        } else if (this.price < book.price) {
            return -1;
        } else {
            return 0;
        }
    }

    @Override
    public boolean equals(Object obj) {
        if (obj instanceof Book) {
            Book book = (Book) obj;
            return this.price == book.price;
        } else {
            return false;
        }
    }
}

SortSearchMainClass类：

import java.util.LinkedList;
import java.util.ListIterator;

public class SortSearchMainClass {
    public static void main(String[] args) {
        LinkedList<Book> bookList = new LinkedList<>();
        bookList.add(new Book(20));
        bookList.add(new Book(30));
        bookList.add(new Book(10));

        Book newBook = new Book(10);
        boolean isEqual = false;

        ListIterator<Book> iterator = bookList.listIterator();
        while (iterator.hasNext()) {
            Book book = iterator.next();
            if (book.equals(newBook)) {
                isEqual = true;
                break;
            }
        }

        if (isEqual) {
            System.out.println("链表中存在和新书价格相等的书。");
        } else {
            System.out.println("链表中不存在和新书价格相等的书。");
        }

        bookList.sort(null);
        System.out.println("排序后的链表：");
        for (Book book : bookList) {
            System.out.println(book.getPrice());
        }
    }
}

3. 数据库管理系统

连接数据库：

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class DatabaseUtil {
    private static final String JDBC_DRIVER = "com.mysql.cj.jdbc.Driver";
    private static final String DB_URL = "jdbc:mysql://localhost:3306/Book?useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=UTC";
    private static final String USER = "root";
    private static final String PASS = "123456";

    public static Connection getConnection() {
        Connection conn = null;
        try {
            Class.forName(JDBC_DRIVER);
            conn = DriverManager.getConnection(DB_URL, USER, PASS);
        } catch (SQLException | ClassNotFoundException e) {
            e.printStackTrace();
        }
        return conn;
    }
}

查询并计算平均价格：

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class QueryPrice {
    public static void main(String[] args) {
        String sql = "SELECT price FROM bookList ORDER BY RAND() LIMIT 10";
        try (Connection conn = DatabaseUtil.getConnection();
             PreparedStatement pstmt = conn.prepareStatement(sql);
             ResultSet rs = pstmt.executeQuery()) {
            double sum = 0;
            int count = 0;
            while (rs.next()) {
                double price = rs.getDouble("price");
                sum += price;
                count++;
            }
            double average = sum / count;
            System.out.println("10条记录的平均价格为：" + average);
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

实验目标 掌握Java Swing图形用户界面编程 实验步骤 1. 实现页面菜单，菜单项包括按名字读取、按学号读取、按班级读取； 2. 实现搜索框，用于输入名字或学号，根据名字或学号查询学生信息； 3. 实现班级下拉列表，用于选择班级并按班级查询学生信息。 4. 实现学生信息展示功能，展示从数据库中查询到的学生信息

；

以下是一个简单的Java Swing图形用户界面编程示例，实现了以上的四个功能：

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.sql.*;

public class StudentInfoGUI extends JFrame implements ActionListener {
    private static final String DB_URL = "jdbc:mysql://localhost:3306/student_db";
    private static final String DB_USER = "root";
    private static final String DB_PASSWORD = "root";
    private static final String[] CLASS_OPTIONS = {"Class 1", "Class 2", "Class 3"};

    private JLabel nameLabel, idLabel, classLabel;
    private JTextField nameField, idField;
    private JComboBox<String> classComboBox;
    private JButton searchButton;
    private JTextArea resultArea;

    public StudentInfoGUI() {
        super("Student Info");

        // 创建菜单栏
        JMenuBar menuBar = new JMenuBar();
        JMenu fileMenu = new JMenu("File");
        JMenuItem nameItem = new JMenuItem("Search by Name");
        JMenuItem idItem = new JMenuItem("Search by ID");
        JMenuItem classItem = new JMenuItem("Search by Class");
        nameItem.addActionListener(this);
        idItem.addActionListener(this);
        classItem.addActionListener(this);
        fileMenu.add(nameItem);
        fileMenu.add(idItem);
        fileMenu.add(classItem);
        menuBar.add(fileMenu);
        setJMenuBar(menuBar);

        // 创建搜索面板
        JPanel searchPanel = new JPanel(new FlowLayout(FlowLayout.LEFT));
        nameLabel = new JLabel("Name:");
        idLabel = new JLabel("ID:");
        nameField = new JTextField(10);
        idField = new JTextField(10);
        searchButton = new JButton("Search");
        searchButton.addActionListener(this);
        searchPanel.add(nameLabel);
        searchPanel.add(nameField);
        searchPanel.add(idLabel);
        searchPanel.add(idField);
        searchPanel.add(searchButton);

        // 创建班级下拉列表
        classLabel = new JLabel("Class:");
        classComboBox = new JComboBox<>(CLASS_OPTIONS);
        classComboBox.addActionListener(this);

        // 创建结果文本域
        resultArea = new JTextArea(20, 50);
        resultArea.setEditable(false);

        // 将组件添加到容器中
        Container contentPane = getContentPane();
        contentPane.setLayout(new BorderLayout());
        contentPane.add(searchPanel, BorderLayout.NORTH);
        JPanel classPanel = new JPanel();
        classPanel.add(classLabel);
        classPanel.add(classComboBox);
        contentPane.add(classPanel, BorderLayout.WEST);
        contentPane.add(new JScrollPane(resultArea), BorderLayout.CENTER);

        setSize(600, 400);
        setLocationRelativeTo(null);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == searchButton) {
            String name = nameField.getText().trim();
            String id = idField.getText().trim();
            String className = (String) classComboBox.getSelectedItem();
            search(name, id, className);
        } else if (e.getActionCommand().equals("Search by Name")) {
            nameField.requestFocus();
        } else if (e.getActionCommand().equals("Search by ID")) {
            idField.requestFocus();
        } else if (e.getActionCommand().equals("Search by Class")) {
            classComboBox.requestFocus();
        }
    }

    private void search(String name, String id, String className) {
        resultArea.setText("");
        String sql = "SELECT * FROM students WHERE name LIKE ? AND id LIKE ? AND class LIKE ?";
        try (Connection conn = DriverManager.getConnection(DB_URL, DB_USER, DB_PASSWORD);
             PreparedStatement stmt = conn.prepareStatement(sql)) {
            stmt.setString(1, "%" + name + "%");
            stmt.setString(2, "%" + id + "%");
            stmt.setString(3, "%" + className + "%");
            ResultSet rs = stmt.executeQuery();
            while (rs.next()) {
                String result = String.format("Name: %s\nID: %s\nClass: %s\nScore: %d\n\n",
                        rs.getString("name"), rs.getString("id"), rs.getString("class"), rs.getInt("score"));
                resultArea.append(result);
            }
            if (resultArea.getText().isEmpty()) {
                resultArea.setText("No records found.");
            }
        } catch (SQLException ex) {
            ex.printStackTrace();
            JOptionPane.showMessageDialog(this, "Error: " + ex.getMessage(), "Error", JOptionPane.ERROR_MESSAGE);
        }
    }

    public static void main(String[] args) {
        StudentInfoGUI gui = new StudentInfoGUI();
        gui.setVisible(true);
    }
}

在本示例中，我们使用了Java Swing的各种组件，如JLabel、JTextField、JComboBox、JButton、JTextArea等，同时还实现了ActionListener接口以响应用户事件。在搜索函数中，我们使用了Java JDBC连接MySQL数据库，并使用PreparedStatement执行带参数的SQL查询语句，以避免SQL注入攻击。