中间的房间周围(东南西北)有四个房间，请编写Java类表达这种关系，同时给房间类提供一个方法，能够从某一出口出来进入该出口对应的房间

要表达一个中间房间四周有四个房间的关系，我们可以定义一个名为`FourWallsRoom`的类，它继承自一个基础的`Room`类，同时增加一个属性来表示中心位置以及四个方向的出口。这里是一个简单的示例：

import java.util.HashMap;
import java.util.Map;

class Direction {
    static final String NORTH = "north";
    static final String SOUTH = "south";
    static final String EAST = "east";
    static final String WEST = "west";

    // 可以考虑使用枚举替代字符串，增强类型安全
}

class BaseRoom {
    private int id;
    private String name;

    // ... 省略Room类的其他属性和构造函数
}

public class FourWallsRoom extends BaseRoom {
    private Map<String, Room> exits; // 使用Map保存四个方向的出口

    public FourWallsRoom(int id, String name) {
        super(id, name);
        exits = new HashMap<>();
        exits.put(Direction.NORTH, createAdjacentRoom(this, Direction.SOUTH));
        exits.put(Direction.SOUTH, createAdjacentRoom(this, Direction.NORTH));
        exits.put(Direction.EAST, createAdjacentRoom(this, Direction.WEST));
        exits.put(Direction.WEST, createAdjacentRoom(this, Direction.EAST));
    }

    private Room createAdjacentRoom(Room currentRoom, Direction direction) {
        // 创建新房间并将其添加到当前房间的出口列表中
        Room adjacentRoom = new BaseRoom(); // 实际项目中应根据需求生成相应类型的房间
        currentRoom.