BikeManage下单车列表删空后判断

ss：如果单车列表里面的单车删完了，值就为空，需要判断

package com.javasm.service.impl;

import com.javasm.bean.Bike;
import com.javasm.bean.BikeCompany;
import com.javasm.constants.BikeConstants;
import com.javasm.service.BikeService;

import java.util.Arrays;
import java.util.Date;
import java.util.Scanner;

public class BikeServiceImpl implements BikeService {
    @Override
    public void showBike(BikeCompany[] bikeCompanies) {
        System.out.println("迷你共享单车管理系统>>>管理员操作>>>查看单车");
        for (BikeCompany bikeCompany : bikeCompanies) {
            System.out.println(bikeCompany);
            //该公司下单车信息
            Bike[] bikes = bikeCompany.getBikes();
            if (bikes == null) {
                System.out.println("[该单车品牌下没有任何的单车信息！]");
                continue;
            }
            for (Bike bike : bikes) {
                System.out.println(bike);
            }
            System.out.println("---------------------------------------------------------------------");
        }
    }

    @Override
    public void putBike(BikeCompany[] bikeCompanies, Scanner scanner) {
        System.out.println("迷你共享单车管理系统>>>管理员操作>>>投放单车");
        //显示公司列表
        for (BikeCompany bikeCompany : bikeCompanies) {
            System.out.println(bikeCompany.getCompanyId() + "-->" + bikeCompany.getCompanyName());
        }
        //选择单车品牌
        System.out.println("请输入要操作的单车品牌：");
        int inputCompanyId = scanner.nextInt();
        //根据品牌id查找品牌信息
        BikeCompany bikeCompany = getBikeCompanyById(inputCompanyId, bikeCompanies);
        //先判断
        if (bikeCompany == null) {
            System.out.println("[投放失败，该单车品牌不存在！]");
            return;
        }
        //允许投放
        System.out.println("请输入要投放的单车数量：");
        int count = scanner.nextInt();
        //获取单车品牌下的单车列表
        Bike[] putBikes = bikeCompany.getBikes(); //001

       //如果单车列表里面的单车删完了，值就为空，需要判断
        //扩容之前的数组的长度
        int oldLength = checkBikes(putBikes) ? 0 : putBikes.length;
        //扩容之前最后一个单车的编号
        int lastId = checkBikes(putBikes) ? getStartId(bikeCompany.getCompanyName()) : putBikes[oldLength - 1].getBikeId();
        //扩容
        putBikes = checkBikes(putBikes) ? new Bike[count] : Arrays.copyOf(putBikes, putBikes.length + count);  //002
        //循环来存入单车对象
        for (int i = oldLength; i < putBikes.length; i++) {
            lastId = ++lastId;
            putBikes[i] = new Bike(lastId, bikeCompany.getCompanyName() + lastId, BikeConstants.UN_LEND_STATE,
                    null, null);
        }
        //将扩容之后的数组反填充
        bikeCompany.setBikes(putBikes);
        //总数
        bikeCompany.setSum(putBikes.length);
        System.out.println("投放<" + count + ">辆<" + bikeCompany.getCompanyName() + ">车成功！");
    }

    @Override
    public void deleteBike(BikeCompany[] bikeCompanies, Scanner scanner) {
        System.out.println("迷你共享单车管理系统>>>管理员操作>>>删除单车");
        //显示公司列表
        for (BikeCompany bikeCompany : bikeCompanies) {
            System.out.println(bikeCompany.getCompanyId() + "-->" + bikeCompany.getCompanyName());
        }
        //选择单车品牌
        System.out.println("请输入要操作的单车品牌：");
        int inputCompanyId = scanner.nextInt();
        //根据品牌id查找品牌信息
        BikeCompany bikeCompany = getBikeCompanyById(inputCompanyId, bikeCompanies);


        //先判断
        if (bikeCompany == null) {
            System.out.println("[删除失败，该单车品牌不存在！]");
            return;
        }
        int count = 0;  //统计未借出数量
        Bike[] deleteBikes = bikeCompany.getBikes();
        if (deleteBikes == null) {
            System.out.println("[该单车品牌下没有任何的单车信息！]");
            return;
        }
        //展示该品牌的未借出的单车信息
        for (Bike deleteBike : deleteBikes) {
            if (deleteBike.getBikeState() == BikeConstants.UN_LEND_STATE) {
                System.out.println(deleteBike);
                count++;
            }
        }
        if (count == 0) {
            System.out.println("[该品牌下没有任何可以删除的车辆！]");
            return;
        }
        //开始删除
        System.out.println("请输入要删除的单车编号：");
        int bikeId = scanner.nextInt();
        //根据单车编号查找对应的索引位置
        int index = getBikeIndexById(deleteBikes, bikeId);
        //先判断
        if (index == -1) {
            System.out.println("[删除失败，该单车不存在！]");
            return;
        }
        //判断状态
        Bike deleteBike = deleteBikes[index];
        if (deleteBike.getBikeState() == BikeConstants.LEND_STATE) {
            System.out.println("[删除失败，该单车已借出！]");
            return;
        }
        //允许删除
        for (int i = index; i < deleteBikes.length - 1; i++) {
            //后一个元素覆盖前一个
            deleteBikes[i] = deleteBikes[i + 1];
        }
        //缩容
        deleteBikes = Arrays.copyOf(deleteBikes, deleteBikes.length - 1);
       //长度为0，给null
        if (deleteBikes.length == 0) {
            bikeCompany.setBikes(null);
            bikeCompany.setSum(0);
        } else {
            //反填充
            bikeCompany.setBikes(deleteBikes);
            bikeCompany.setSum(deleteBikes.length);
        }
        System.out.println("[删除<" + bikeCompany.getCompanyName() + ">公司下的<" + deleteBike.getBikeName() + ">车成功!]");
    }

    /**
     * 根据单车编号查找对应索引
     *
     * @param bikes
     * @param bikeId
     * @return
     */
    private int getBikeIndexById(Bike[] bikes, int bikeId) {
        for (int i = 0; i < bikes.length; i++) {
            if (bikeId == bikes[i].getBikeId()) {
                return i;
            }
        }
        return -1;
    }

    /**
     * 根据品牌编号查找品牌信息
     *
     * @param id
     * @param bikeCompanies
     * @return
     */
    private BikeCompany getBikeCompanyById(int id, BikeCompany[] bikeCompanies) {
        for (BikeCompany bikeCompany : bikeCompanies) {
            if (id == bikeCompany.getCompanyId()) {
                return bikeCompany;
            }
        }
        return null;
    }

    /**
     * 根据公司名称获取起始ID
     *
     * @param name
     * @return
     */
    private int getStartId(String name) {
        switch (name) {
            case BikeConstants.OFO:
                return BikeConstants.OFO_START_ID;
            case BikeConstants.HALO:
                return BikeConstants.HALO_START_ID;
            case BikeConstants.MO_BAI:
                return BikeConstants.MO_BAI_START_ID;
        }
        return 0;
    }

    /**
     * 判断单车列表
     *
     * @param bikes
     * @return
     */
    private boolean checkBikes(Bike[] bikes) {
        return bikes == null || bikes.length == 0;
    }
}

 

package com.javasm.constants;

import javax.swing.plaf.synth.SynthTextAreaUI;

/**
 * @Author：liulei
 * @Version：1.0
 * @Date：2022/11/24-16:13
 * @Since：jdk1.8
 * @Description：
 */
public class BikeConstants {
    //公司名称
    public static final String OFO = "ofo小黄车";
    public static final String MO_BAI = "摩拜";
    public static final String HALO = "哈罗";

    //单车借出状态（0、未借出  1、已借出）
    public static final int LEND_STATE = 1;
    public static final int UN_LEND_STATE = 0;

    //单车的起始ID
    public static final int OFO_START_ID = 99;
    public static final int MO_BAI_START_ID = 199;
    public static final int HALO_START_ID = 299;
}