【Java】SE练习项目 —》图书管理系统

小鱼儿 2023-09-28 21:46 97阅读 0赞

![在这里插入图片描述][078b66f87e3c4e309d7f34d79c5776c4.gif_pic_center]✨**博客主页:**[ **XIN-XIANG荣**][_XIN-XIANG]  
✨**系列专栏:**[**【Java SE】**][Java SE]  
✨**一句短话:** **难在坚持,贵在坚持,成在坚持!**

#### 文章目录 ####

*  前言
 *  1. 项目需求
 *  2. 实现思路
 *  3. 代码实现
 *   *  包的设计
     *  book包
     *   *  Book类
         *  BookList类
     *  operations包
     *   *  IOperation接口
         *  AddOperation类
         *  BorrowOperation类
         *  DelOperation类
         *  DisplayOperation类
         *  ExitOperation类
         *  FindOperation类
         *  ReturnOperation类
     *  user包
     *   *  User类
         *  AdminUser类
         *  NormalUser类
     *  Main类
 *  4. 实现效果
 *   *  管理员
     *  普通用户

## 前言 ##

这篇博客是在学习了一部分Java基础语法之后的练习项目，通过这个小项目的练习，对Java中的类和对象，抽象类和接口，面向对象的继承、多态和封装、组合等进行熟悉理解；抽象出不同的对象，将对象进行合理的设计，完成对象之间的交互，面向对象进行编程。

## 1. 项目需求 ##

图书管理系统，面向管理员和普通用户使用，对管理员的开放的功能有：添加图书，删除图书，查找图书，显示图书和退出程序等；对普通用户的开放的功能有：查找图书，借阅图书，归还图书和退出程序。

## 2. 实现思路 ##

先抽象提取出不同的对象，首先想到的对象是用户和书，

用户可分为管理员和普通用户，将管理员和普通用户共有的属性设置为一个父类User，管理员和普通用户继承User，可以先将父类设置为普通类，在写码过程如果合适可以修改为抽象类；

系统对书进行管理，书本身就可以抽象为一个对象；对多本书进行操作管理，书架也可以抽象为一个对象；所以书和书架用两个类来实现，书架可以设计为一个数组；

这里系统对书进行管理，其实就是对书架对应数组进行操作，不同的操作可以通过一个标准去实现，也就是可以定义一个接口，每一个操作类去实现这个接口，完成向上转型，通过接口实现多态；

然后写代码的过程中思考完善各个对象的成员，最终实例化对象，通过不同对象之间的交互完成管理系统。

## 3. 代码实现 ##

### 包的设计 ###

![img][]

### book包 ###

#### Book类 ####

package book;
    
    public class Book {
        
        private String name;//书名
        private String author;//书的作者
        private int price;//书的价格
        private String type;//书的类型
        private boolean borrowed;//是否被借出，默认false
    
        public Book(String name, String author, int price, String type) {
        
            this.name = name;
            this.author = author;
            this.price = price;
            this.type = type;
        }
    
        public String getName() {
        
            return name;
        }
    
        public void setName(String name) {
        
            this.name = name;
        }
    
        public String getAuthor() {
        
            return author;
        }
    
        public void setAuthor(String author) {
        
            this.author = author;
        }
    
        public int getPrice() {
        
            return price;
        }
    
        public void setPrice(int price) {
        
            this.price = price;
        }
    
        public String getType() {
        
            return type;
        }
    
        public void setType(String type) {
        
            this.type = type;
        }
    
        public Boolean getBorrowed() {
        
            return borrowed;
        }
    
        public void setBorrowed(Boolean borrowed) {
        
            this.borrowed = borrowed;
        }
    
        @Override
        public String toString() {
        
            return "Book{" +
                    "name='" + name + '\'' +
                    ", author='" + author + '\'' +
                    ", price=" + price +
                    ", type='" + type + '\'' +
                    ", borrowed=" + ((borrowed==true) ? "已借出" : "未借出") +
                    '}';
        }
    }

#### BookList类 ####

package book;
    
    public class BookList {
        
        private Book[] books = new Book[100];
        private int usedsize;
        //书架当中默认有三本书
    
        public BookList() {
        
            this.books[0] = new Book("三国演义","罗贯中",66,"小说");
            this.books[1] = new Book("西游记","吴承恩",68,"小说");
            this.books[2] = new Book("红楼梦","曹雪芹",64,"小说");
            this.usedsize = 3;
        }
    
        public int getUsedsize() {
        
            return usedsize;
        }
    
        public void setUsedsize(int usedsize) {
        
            this.usedsize = usedsize;
        }
    
    
        public Book getBooks(int pos){
        
            return this.books[pos];
        }
    
        public void setBooks(Book book, int pos) {
        
            this.books[pos] = book;
        }
    }

### operations包 ###

#### IOperation接口 ####

package operations;
    
    import book.BookList;
    
    public interface IOperation {
        
        void work(BookList bookList);
    }

#### AddOperation类 ####

package operations;
    
    import book.Book;
    import book.BookList;
    
    import java.util.Scanner;
    
    public class AddOperation implements IOperation{
        
        @Override
        public void work(BookList bookList) {
        
            System.out.println("新增图书");
            //输入图书信息
            System.out.println("输入新增图书名称:");
            Scanner scanner = new Scanner(System.in);
            String name = scanner.nextLine();
            System.out.println("输入新增图书作者:");
            String author = scanner.nextLine();
            System.out.println("输入新增图书价格:");
            int price = scanner.nextInt();
            scanner.nextLine();
            System.out.println("输入新增图书类型:");
            String type = scanner.nextLine();
    
            Book book = new Book(name, author, price, type);
            //获取存书位置
            int currentSize = bookList.getUsedsize();
            //把书放到书架（数组）
            bookList.setBooks(book, currentSize);
            //书的总数加1
            bookList.setUsedsize(currentSize+1);
            System.out.println("添加成功！");
        }
    }

#### BorrowOperation类 ####

package operations;
    
    import book.Book;
    import book.BookList;
    
    import java.util.Scanner;
    
    public class BorrowOperation implements IOperation{
        
        @Override
        public void work(BookList bookList) {
        
            System.out.println("借阅图书");
            System.out.println("输入要借阅图书的名称:");
            Scanner scanner = new Scanner(System.in);
            String name = scanner.nextLine();
            int currentSize = bookList.getUsedsize();
    
            for (int i = 0; i < currentSize; i++) {
        
                Book book = bookList.getBooks(i);
                if (name.equals(book.getName())){
        
                    if(book.getBorrowed()){
        
                        System.out.println("该书已经被借出！");
                        return;
                    }else {
        
                        book.setBorrowed(true);
                        System.out.println("借阅成功！");
                        return;
                    }
                }
            }
            System.out.println("没有找到你要借阅的书");
        }
    }

#### DelOperation类 ####

package operations;
    
    import book.Book;
    import book.BookList;
    
    import java.util.Scanner;
    
    public class DelOperation implements IOperation{
        
        @Override
        public void work(BookList bookList) {
        
            System.out.println("删除图书");
            System.out.println("输入要删除图书的名称:");
            Scanner scanner = new Scanner(System.in);
            String name = scanner.nextLine();
            int currentSize = bookList.getUsedsize();
    
            //找到并记录要删除书的下标
            int index = -1;
            for (int i = 0; i < currentSize; i++) {
        
                Book book = bookList.getBooks(i);
                if (name.equals(book.getName())){
        
                    index = i;
                    break;
                }
            }
            if(-1 == index) {
        
                System.out.println("没有找到要删除的这本书！");
            }else {
        
                for (int i = index; i < currentSize-1; i++) {
        
                    Book book = bookList.getBooks(i+1);
                    bookList.setBooks(book, i);
                }
                //每次删除，都要将原来最后一本书位置的引用置空
                bookList.setBooks(null,currentSize-1);
                bookList.setUsedsize(currentSize-1);
                System.out.println("删除成功");
            }
        }
    }

#### DisplayOperation类 ####

package operations;
    
    import book.Book;
    import book.BookList;
    
    import java.util.Scanner;
    
    public class DisplayOperation implements IOperation{
        
        @Override
        public void work(BookList bookList) {
        
            System.out.println("显示图书");
            int currentSize = bookList.getUsedsize();
    
            for (int i = 0; i < currentSize; i++) {
        
                Book book = bookList.getBooks(i);
                System.out.println(book);
            }
        }
    }

#### ExitOperation类 ####

package operations;
    
    import book.BookList;
    
    public class ExitOperation implements IOperation{
        
        @Override
        public void work(BookList bookList) {
        
            System.out.println("退出系统");
            System.exit(0);
        }
    }

#### FindOperation类 ####

import book.Book;
    import book.BookList;
    
    import java.util.Scanner;
    
    public class FindOperation implements IOperation{
        
        @Override
        public void work(BookList bookList) {
        
            System.out.println("查找图书");
            System.out.println("输入要查找图书的名称:");
            Scanner scanner = new Scanner(System.in);
            String name = scanner.nextLine();
            int currentSize = bookList.getUsedsize();
    
            for (int i = 0; i < currentSize; i++) {
        
                Book book = bookList.getBooks(i);
                if (name.equals(book.getName())){
        
                    System.out.println("找到了，该书信息如下:");
                    System.out.println(book);
                    return;
                }
            }
            System.out.println("没有找到这本书！");
        }
    }

#### ReturnOperation类 ####

package operations;
    
    import book.Book;
    import book.BookList;
    
    import java.util.Scanner;
    
    public class ReturnOperation implements IOperation{
        
        @Override
        public void work(BookList bookList) {
        
            System.out.println("归还图书");
            System.out.println("输入要归还图书的名称:");
            Scanner scanner = new Scanner(System.in);
            String name = scanner.nextLine();
            int currentSize = bookList.getUsedsize();
    
            for (int i = 0; i < currentSize; i++) {
        
                Book book = bookList.getBooks(i);
                if (name.equals(book.getName())){
        
                    if(book.getBorrowed()){
        
                        book.setBorrowed(false);
                        System.out.println("归还成功！");
                        return;
    
                    }else {
        
                        System.out.println("该书未借出！");
                        return;
                    }
                }
            }
            System.out.println("没有找到你要归还的书");
        }
    }

### user包 ###

#### User类 ####

public abstract class User {
        
        protected String name;
        protected IOperation[] iOperation;
    
        public User(String name) {
        
            this.name = name;
        }
        public abstract int menu();
        public void doOperation(int choice, BookList bookList){
        
            iOperation[choice].work(bookList);
        }
    }

#### AdminUser类 ####

package user;
    
    import operations.*;
    
    import java.util.Scanner;
    
    public class AdminUser extends User{
        
        public AdminUser(String name) {
        
            super(name);
            this.iOperation = new IOperation[]{
        
                    new ExitOperation(),
                    new FindOperation(),
                    new AddOperation(),
                    new DelOperation(),
                    new DisplayOperation()
            };
        }
    
        @Override
        public int menu() {
        
            System.out.println("---------------------------------");
            System.out.println("Hello 管理员:>"+""+name+" 欢迎来到图书管理系统！");
            System.out.println("      1.查找图书  2.新增图书");
            System.out.println("      3.删除图书  4.显示图书");
            System.out.println("           0.退出系统");
            System.out.println("---------------------------------");
            System.out.println("请输入你的操作:");
            Scanner scanner = new Scanner(System.in);
            int choice = scanner.nextInt();
            return choice;
        }
    }

#### NormalUser类 ####

package user;
    
    import operations.*;
    
    import java.util.Scanner;
    
    public class NormalUser extends User{
        
        public NormalUser(String name) {
        
            super(name);
            this.iOperation = new IOperation[]{
        
                    new ExitOperation(),
                    new FindOperation(),
                    new BorrowOperation(),
                    new ReturnOperation()
            };
        }
    
        @Override
        public int menu() {
        
            System.out.println("---------------------------------");
            System.out.println("Hello 用户:>"+name+" 欢迎来到图书管理系统！");
            System.out.println("      1.查找图书  2.借阅图书");
            System.out.println("      3.归还图书  0.退出系统");
            System.out.println("---------------------------------");
            System.out.println("请输入你的操作:");
            Scanner scanner = new Scanner(System.in);
            int choice = scanner.nextInt();
            return choice;
        }
    }

### Main类 ###

import book.BookList;
    import user.AdminUser;
    import user.NormalUser;
    import user.User;
    
    import java.util.Scanner;
    
    public class Main {
        
        public static User login(){
        
            System.out.println("请输入你的姓名:");
            Scanner scanner = new Scanner(System.in);
            String userName = scanner.nextLine();
            System.out.println("请确认你的身份:> |1->管理员|0->普通用户|");
            int choice = scanner.nextInt();
            if(1==choice){
        
                return new AdminUser(userName);
            }else{
        
                return new NormalUser(userName);
            }
        }
    
        public static void main(String[] args) {
        
            //准备数据
            BookList bookList = new BookList();
            //登录
            User user = login();
    
            while (true) {
        
                int choice = user.menu();
                user.doOperation(choice, bookList);
            }
        }
    }

## 4. 实现效果 ##

### 管理员 ###

![img][img 1]

### 普通用户 ###

![img][img 2]

[078b66f87e3c4e309d7f34d79c5776c4.gif_pic_center]: https://img-blog.csdnimg.cn/078b66f87e3c4e309d7f34d79c5776c4.gif#pic_center
[_XIN-XIANG]: https://blog.csdn.net/Trong_?spm=1000.2115.3001.5343
[Java SE]: https://blog.csdn.net/trong_/category_11933690.html?spm=1001.2014.3001.5482
[img]: https://img-blog.csdnimg.cn/img_convert/46c8d67a5bd6608a4a18523cde13dd55.png
[img 1]: https://img-blog.csdnimg.cn/img_convert/dd117f08617cf2228e854b5ee61a4101.gif
[img 2]: https://img-blog.csdnimg.cn/img_convert/77eda157208678d5a982962a012a6f70.gif