用Java写一个连接数据库的学生宿舍管理系统

好的，以下是一个简单的Java连接MySQL数据库实现学生宿舍管理系统的示例：

首先，需要导入MySQL的JDBC驱动程序，可以在Maven中添加以下依赖项：

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.23</version>
</dependency>

接下来，创建一个名为`Student`的Java类，用于存储学生的信息：

public class Student {
    private int id;
    private String name;
    private String gender;
    private String dormitory;

    public Student(int id, String name, String gender, String dormitory) {
        this.id = id;
        this.name = name;
        this.gender = gender;
        this.dormitory = dormitory;
    }

    // getters and setters
}

然后，创建一个名为`DatabaseConnection`的Java类，用于连接MySQL数据库：

import java.sql.*;

public class DatabaseConnection {
    private Connection connection;

    public DatabaseConnection(String url, String user, String password) throws SQLException {
        connection = DriverManager.getConnection(url, user, password);
    }

    public void close() throws SQLException {
        connection.close();
    }

    public void insertStudent(Student student) throws SQLException {
        PreparedStatement statement = connection.prepareStatement("INSERT INTO students (id, name, gender, dormitory) VALUES (?, ?, ?, ?)");
        statement.setInt(1, student.getId());
        statement.setString(2, student.getName());
        statement.setString(3, student.getGender());
        statement.setString(4, student.getDormitory());
        statement.executeUpdate();
    }

    public Student getStudentById(int id) throws SQLException {
        PreparedStatement statement = connection.prepareStatement("SELECT * FROM students WHERE id = ?");
        statement.setInt(1, id);
        ResultSet resultSet = statement.executeQuery();

        if (resultSet.next()) {
            return new Student(
                    resultSet.getInt("id"),
                    resultSet.getString("name"),
                    resultSet.getString("gender"),
                    resultSet.getString("dormitory")
            );
        } else {
            return null;
        }
    }

    public void updateStudent(Student student) throws SQLException {
        PreparedStatement statement = connection.prepareStatement("UPDATE students SET name = ?, gender = ?, dormitory = ? WHERE id = ?");
        statement.setString(1, student.getName());
        statement.setString(2, student.getGender());
        statement.setString(3, student.getDormitory());
        statement.setInt(4, student.getId());
        statement.executeUpdate();
    }

    public void deleteStudent(int id) throws SQLException {
        PreparedStatement statement = connection.prepareStatement("DELETE FROM students WHERE id = ?");
        statement.setInt(1, id);
        statement.executeUpdate();
    }
}

在`DatabaseConnection`类中，我们定义了几种常见的数据库操作，例如插入、查找、更新和删除学生信息。

最后，创建一个`Main`类，用于测试我们的数据库连接和操作：

public class Main {
    public static void main(String[] args) {
        try {
            DatabaseConnection connection = new DatabaseConnection("jdbc:mysql://localhost:3306/dormitory", "root", "password");
            Student student1 = new Student(1, "张三", "男", "1号楼101");
            Student student2 = new Student(2, "李四", "女", "2号楼201");

            // 插入学生信息
            connection.insertStudent(student1);
            connection.insertStudent(student2);

            // 查找学生信息
            Student student3 = connection.getStudentById(1);
            System.out.println(student3.getName()); // 输出：张三

            // 更新学生信息
            student1.setDormitory("1号楼105");
            connection.updateStudent(student1);

            // 删除学生信息
            connection.deleteStudent(2);

            connection.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

在`Main`类中，我们创建了两个学生对象并插入到数据库中，然后查找ID为1的学生信息并输出姓名，然后更新ID为1的学生的宿舍信息和删除ID为2的学生信息，最后关闭数据库连接。

以上是一个简单的使用Java连接MySQL数据库实现学生宿舍管理系统的示例，具体的实现可能因为项目需求而有所不同。