实现图书管理系统

1. 图书管理系统菜单

如上图给用户选项

1. 管理员

2. 普通用户

2. 实现基本框架

1.先选择book包，new两个类 book  bookList 

在book类中定义书的基本属性，并重写toString方法，构造方法 ，以及实现成员变量的Getter and Setter方法

在bookList类中定义一个一个数组储存图书Book[]，以及一个usedSize记录图书的数量，重写构造方法，并实现成员变量的Getter and Setter方法

 2. 选择operation包，创建一个接口并创建work方法（抽象方法），规范包中的类

命名以上的类，并重写work方法

3. 选择user包，创建User类，AdminUser类，NormalUser类，让前者作为父类

在User类中定义name接受用户名，并创建抽象方法menu模拟进入程序

public abstract class User {
    protected String name;
    public User(String name) {
        this.name = name;
    }
    public abstract int menu();
}

程序的入口 

package book;
import user.*;
import java.util.Scanner;

public class Main {
    public static User login(){
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入你的名字: ");
        String name = scanner.nextLine();
        System.out.println("请输入你的身份: ");
        System.out.println("1. 管理员        0. 普通用户");
        int choice = scanner.nextInt();
        if(choice == 1){
            AdminUser adminUser = new AdminUser(name);
            return adminUser;
        }else{
            NormalUser normalUser = new NormalUser(name);
            return normalUser;
        }
    }
    public static void main(String[] args) {
        BookList bookList = new BookList();
        User user = login();
        while (true){
            int choice = user.menu();
            user.doOperation(choice,bookList);
        }
    }
}

3. 实现业务 

3.1 借阅图书

package operation;

import book.*;

import java.util.Scanner;

public class BorrowedOperation implements IOperation{
    public void work(BookList booklist) {
        System.out.println("借阅图书");
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入书名；");
        String name = scanner.nextLine();
        int currentSize = booklist.getUsedSize();
        for (int i = 0; i < currentSize; i++) {
            Book book1 = booklist.getBook(i);
            if(book1.getName().equals(name)) {
               if(!book1.isBorrowed()){
                   book1.setBorrowed(true);
                   System.out.println("借阅成功");
               }else{
                   System.out.println("这本图书已经被借走了：");
               }
               return;
            }
        }
        System.out.println("书架上内有你要借阅的图书：");
    }
}

3.2 查找图书

package operation;

import book.*;

import java.util.Scanner;

public class FindOperation implements IOperation{
    public void work(BookList booklist) {
        System.out.println("查找图书");
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入你要查找的图书: ");
        String name = scanner.nextLine();
        int currentSize = booklist.getUsedSize();
        for (int i = 0; i < booklist.getUsedSize(); i++) {
            Book book = booklist.getBook(i);
            if(book.getName().equals(name)){
                System.out.println("找到了你要找的书: ");
                System.out.println(book);
                return;
            }
        }
        System.out.println("书架上没有这本书！");
    }
}

3.3 归还图书

package operation;

import book.*;

import java.util.Scanner;

public class ReturnOperation implements IOperation{
    public void work(BookList booklist) {
        System.out.println("归还图书");
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入书名；");
        String name = scanner.nextLine();
        int currentSize = booklist.getUsedSize();
        for (int i = 0; i < currentSize; i++) {
            Book book1 = booklist.getBook(i);
            if(book1.getName().equals(name)){
                if(!book1.isBorrowed()){
                   System.out.println("这本图书没有被借走");
                }else{
                   book1.setBorrowed(false);
                    System.out.println("归还成功");
                }
                return;
            }
        }
        System.out.println("没有你要归还的图书");
    }
}

3.4 新增图书

package operation;

import book.*;

import java.util.Scanner;

public class AddOperation implements IOperation{
    @Override
    public void work(BookList booklist) {
        System.out.println("增加图书");
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入书名；");
        String name = scanner.nextLine();
        System.out.println("请输入作者名；");
        String author = scanner.nextLine();
        System.out.println("请输入价格；");
        int price = scanner.nextInt();
        scanner.nextLine();
        System.out.println("请输入类型；");
        String style = scanner.nextLine();
        Book book = new Book(name,author,price,style);
        int currentSize = booklist.getUsedSize();
        for (int i = 0; i < currentSize; i++) {
            Book book1 = booklist.getBook(i);
            if(book1.getName().equals(name)){
                System.out.println("书架上已经有这本书了");
                return;
            }
        }
        booklist.setBook(currentSize,book);
        booklist.setUsedSize(currentSize+1);
    }
}

3.5 删除图书

package operation;

import book.*;

import java.util.Scanner;

public class DelOperation implements IOperation{
    public void work(BookList booklist) {
        System.out.println("删除图书");
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入你要删除的图书；");
        String name = scanner.nextLine();
        int currentSize = booklist.getUsedSize();
        if(currentSize == 0){
            System.out.println("书架为空：");
            return;
        }
        int index = -1;
        for (int i = 0; i < currentSize; i++) {
            Book book1 = booklist.getBook(i);
            if(book1.getName().equals(name)) {
                index = i;
                break;
            }
        }
        if(index == -1){
            System.out.println("书架上没有这本书：");
            return;
        }
        for (int i = index; i < currentSize; i++) {
            Book book1 = booklist.getBook(i+1);
            booklist.setBook(i,book1);
        }
        booklist.setUsedSize(currentSize-1);
    }
}

3.6 显示图书

package operation;

import book.*;

public class ShowOperation implements IOperation{
    public void work(BookList booklist) {
        System.out.println("展示图书");
        int currentSize = booklist.getUsedSize();
        for (int i = 0; i < booklist.getUsedSize(); i++) {
            Book book = booklist.getBook(i);
            System.out.println(book);
        }
    }
}

3.7 退出系统

package operation;

import book.Book;
import book.BookList;

public class ExitOperation implements IOperation{
    public void work(BookList booklist) {
        System.out.println("退出系统");
        for (int i = 0; i < booklist.getUsedSize(); i++) {
            booklist.setBook(i,null);
        }
        booklist.setUsedSize(0);
        System.exit(0);
    }
}