Java中如何正确传递包含数组的对象并访问其内部数组

public class ControllerRoute extends Menu { // 继承Menu在此处是不必要的，且可能导致混淆
    Route[] routes;

    public ControllerRoute(int size) {
        routes = new Route[size];
    }
}

public class UpdateAndDelete {
    public Route updateRoutes(int id, ControllerRoute cr) {
        int pos = -1;
        String nwname;
        // 错误发生在这里：cr是一个ControllerRoute对象，而不是一个数组
        for (int i = 0; i < cr.length; i++) { // 错误: cannot find symbol (cr.length)
            if (id == cr[i].getId()) { // 错误: array required, but ControllerRoute found (cr[i])
                pos = i;
            }
        }
        // cr[pos] = new Route(id, nwname); // 同样的错误
        return null;
    }
}

public class ControllerRoute { // 移除不必要的 'extends Menu'
    private Route[] routes; // 建议将成员变量设为private以增强封装性

    public ControllerRoute(int size) {
        routes = new Route[size];
    }

    // 新增的Getter方法，用于获取内部的routes数组
    public Route[] getRoutes() {
        return routes;
    }

    // 假设Route类有getId()方法，这里也需要一个方法来填充数组元素
    public void addRoute(int index, Route route) {
        if (index >= 0 && index < routes.length) {
            routes[index] = route;
        } else {
            System.err.println("Index out of bounds for adding route.");
        }
    }
}

import javax.swing.JOptionPane;

public class Menu {
    // 假设ControllerRoute的构造函数可以初始化一些Route对象
    private ControllerRoute cr = new ControllerRoute(100);
    UpdateAndDelete ud = new UpdateAndDelete();

    // 示例：初始化一些测试数据
    public Menu() {
        for (int i = 0; i < 5; i++) {
            cr.addRoute(i, new Route(i + 1, "Route " + (i + 1)));
        }
    }

    public void updateRoute() {
        // ControllerRoute ur = new ControllerRoute(0); // 这个变量在此处似乎没有用到
        int id;
        try {
            id = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter an Id"));
            // 正确的做法：通过cr.getRoutes()获取并传递数组
            ud.updateRoutes(id, cr.getRoutes());
        } catch (NumberFormatException e) {
            JOptionPane.showMessageDialog(null, "Invalid ID. Please enter a number.");
        }
    }
}

import javax.swing.JOptionPane;

public class UpdateAndDelete {

    public Route updateRoutes(int id, Route[] routes) { // 参数类型改为Route[]
        int pos = -1;
        String nwname = null; // 初始化nwname

        // 现在routes是一个真正的数组，可以正常使用.length和[]操作符
        for (int i = 0; i < routes.length; i++) {
            // 需要处理数组元素可能为null的情况
            if (routes[i] != null && id == routes[i].getId()) {
                pos = i;
                break; // 找到后即可退出循环
            }
        }

        if (pos != -1) {
            nwname = JOptionPane.showInputDialog(null, "Enter new name for ID " + id);
            if (nwname != null && !nwname.trim().isEmpty()) {
                // 更新数组中的Route对象
                routes[pos] = new Route(id, nwname);
                JOptionPane.showMessageDialog(null, "Route ID " + id + " updated successfully.");
                return routes[pos];
            } else {
                JOptionPane.showMessageDialog(null, "New name cannot be empty.");
            }
        } else {
            JOptionPane.showMessageDialog(null, "Route with ID " + id + " not found.");
        }
        return null;
    }
}

public class Route {
    private int id;
    private String name;

    public Route() {}

    public Route(int id, String name) {
        this.id = id;
        this.name = name;
    }

    // 新增的getId()方法
    public int getId() {
        return id;
    }

    // 示例：toString方法方便打印
    @Override
    public String toString() {
        return "Route [id=" + id + ", name=" + name + "]";
    }
}