如何将postgresql数据库连接到maven项目？

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

public class PostgresqlExample {
    public static void main(String[] args) {
        Connection connection = null;
        Statement statement = null;
        ResultSet resultSet = null;

        try {
            // 连接到数据库
            connection = DriverManager.getConnection("jdbc:postgresql://localhost:5432/数据库名", "用户名", "密码");

            // 创建Statement对象
            statement = connection.createStatement();

            // 执行查询
            resultSet = statement.executeQuery("SELECT * FROM 表名");

            // 处理查询结果
            while (resultSet.next()) {
                // 读取数据
                int id = resultSet.getInt("id");
                String name = resultSet.getString("name");
                // 其他字段...

                // 打印结果
                System.out.println("ID: " + id + ", Name: " + name);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            // 关闭资源
            try {
                if (resultSet != null) {
                    resultSet.close();
                }
                if (statement != null) {
                    statement.close();
                }
                if (connection != null) {
                    connection.close();
                }
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
}