请以java和mysql做一个”码头停泊位系统“

好的，下面是Java和MySQL实现的"码头停泊位系统"的示例代码：

首先，我们需要创建一个数据库和表来存储停泊位信息。可以使用以下SQL语句：

CREATE DATABASE port;
USE port;

CREATE TABLE berth (
  id INT PRIMARY KEY AUTO_INCREMENT,
  name VARCHAR(50),
  capacity INT,
  occupied INT DEFAULT 0
);

这个表包含了停泊位的名称、容量和占用情况。

接下来，我们可以编写Java代码来连接数据库并操作数据。这里我们使用JDBC来连接MySQL数据库。

import java.sql.*;

public class BerthSystem {
  private static final String URL = "jdbc:mysql://localhost:3306/port";
  private static final String USER = "root";
  private static final String PASSWORD = "password";

  public static void main(String[] args) {
    try (Connection conn = DriverManager.getConnection(URL, USER, PASSWORD)) {
      System.out.println("Connected to database");

      // 添加停泊位
      addBerth(conn, "Berth 1", 100);
      addBerth(conn, "Berth 2", 200);

      // 查询停泊位
      listBerths(conn);

      // 更新停泊位
      updateBerth(conn, "Berth 1", 80);

      // 删除停泊位
      deleteBerth(conn, "Berth 2");

      // 再次查询停泊位
      listBerths(conn);
    } catch (SQLException e) {
      e.printStackTrace();
    }
  }

  private static void addBerth(Connection conn, String name, int capacity) throws SQLException {
    String sql = "INSERT INTO berth (name, capacity) VALUES (?, ?)";
    try (PreparedStatement stmt = conn.prepareStatement(sql)) {
      stmt.setString(1, name);
      stmt.setInt(2, capacity);
      stmt.executeUpdate();
      System.out.println("Added berth " + name);
    }
  }

  private static void listBerths(Connection conn) throws SQLException {
    String sql = "SELECT * FROM berth";
    try (Statement stmt = conn.createStatement();
         ResultSet rs = stmt.executeQuery(sql)) {
      while (rs.next()) {
        int id = rs.getInt("id");
        String name = rs.getString("name");
        int capacity = rs.getInt("capacity");
        int occupied = rs.getInt("occupied");
        System.out.println(String.format("Berth %d: %s (Capacity: %d, Occupied: %d)", id, name, capacity, occupied));
      }
    }
  }

  private static void updateBerth(Connection conn, String name, int occupied) throws SQLException {
    String sql = "UPDATE berth SET occupied = ? WHERE name = ?";
    try (PreparedStatement stmt = conn.prepareStatement(sql)) {
      stmt.setInt(1, occupied);
      stmt.setString(2, name);
      stmt.executeUpdate();
      System.out.println("Updated berth " + name);
    }
  }

  private static void deleteBerth(Connection conn, String name) throws SQLException {
    String sql = "DELETE FROM berth WHERE name = ?";
    try (PreparedStatement stmt = conn.prepareStatement(sql)) {
      stmt.setString(1, name);
      stmt.executeUpdate();
      System.out.println("Deleted berth " + name);
    }
  }
}

在这个示例中，我们实现了添加、查询、更新和删除停泊位的功能。通过使用JDBC连接MySQL数据库，我们可以轻松地操作数据库中的数据。

当我们运行这个程序时，它会输出以下内容：

Connected to database
Added berth Berth 1
Added berth Berth 2
Berth 1: Berth 1 (Capacity: 100, Occupied: 0)
Berth 2: Berth 2 (Capacity: 200, Occupied: 0)
Updated berth Berth 1
Deleted berth Berth 2
Berth 1: Berth 1 (Capacity: 100, Occupied: 80)

这表明我们成功地向数据库中添加了两个停泊位，然后查询了它们的信息，并更新了一个停泊位的占用情况和删除了一个停泊位，最后再次查询了停泊位的信息。

希望这个示例能够帮助你实现自己的"码头停泊位系统"！