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前言
该我的项目外围需要:
实现简略登录
管理员端实现下列性能
①查找书籍
②减少书籍
③删除书籍
④展现全副书籍
⑤退出零碎
通用户实现下列性能
①查问书籍
②借阅书籍
③偿还书籍
④退出零碎
我的项目类的设计展现
图书相干的类
Book:定义书籍的信息 BookList:示意书库,外面寄存书籍
package book;
/**
* Created with IntelliJ IDEA
* Details about unstoppable_t:
* User: Administrator
* Date: 2021 -01-19
* Time: 16:54
*/
public class Book {
// 定义成员变量
private String name;
private String author;
private int price;
private String type;
private boolean isBorrowed = false; // 示意书的借阅状态
public Book(String name, String author, int price, String type) {
this.name = name;
this.author = author;
this.price = price;
this.type = type;
// this.isBorrowed = isBorrowed;
}
public String getName() {return name;}
public String getAuthor() {return author;}
public int getPrice() {return price;}
public String getType() {return type;}
public boolean isBorrowed() {return isBorrowed;}
public void setName(String name) {this.name = name;}
public void setAuthor(String author) {this.author = author;}
public void setPrice(int price) {this.price = price;}
public void setType(String type) {this.type = type;}
public void setBorrowed(boolean borrowed) {isBorrowed = borrowed;}
// @Override
// public String toString() {
// return "Book{" +
// "name='" + name + '\'' +
// ", author='" + author + '\'' +
// ", price=" + price +
// ", type='" + type + '\'' +
// ", isBorrowed=" + isBorrowed +
// '}';
// }
@Override
public String toString() {
return "Book{" +
"name='" + name + '\'' +
", author='" + author + '\'' +
", price=" + price +
", type='" + type + '\'' +
((isBorrowed == true) ? "借阅状态: 已借出" : "借阅状态: 未借出") +
'}';
}
}
package book;
/**
* Created with IntelliJ IDEA
* Details about unstoppable_t:
* User: Administrator
* Date: 2021 -01-19
* Time: 16:54
*/
public class BookList {
public int usedSize = 3; // 书架
public Book[] books = new Book[10]; // 书的类型为 Book,用顺数组 book 去存储
public BookList() {books[0] = new Book("三国演义","罗贯中", 100, "小说");
books[1] = new Book("水浒传", "施耐庵", 100, "小说");
books[2] = new Book("西游记", "吴承恩", 100, "小说");
}
// 给指定地位放书
public void setBooks(int pos,Book book) {this.books[pos] = book;
}
// 拿到指定地位的书
public Book getBooks(int pos){return this.books[pos];
}
public int getUsedSize() {return usedSize;}
public void setUsedSize(int usedSize) {this.usedSize = usedSize;}
}
对书库(程序表)操作的类
// 新增
public class AddOperation implements IOperation{
@Override
public void work(BookList booklist) {System.out.println("增加书籍");
Scanner sc = new Scanner(System.in);
System.out.println("请输出书名");
String name = sc.nextLine();
System.out.println("请输出书的作者");
String author = sc.nextLine();
System.out.println("请输出书的价格");
int price = sc.nextInt();
System.out.println("请输出书的类型");
String type = sc.next();
Book newBook = new Book(name,author,price,type); // 构建新书(对象)int size = booklist.getUsedSize(); // 通过 bookList 援用拜访以后程序表长度
booklist.setBooks(size,newBook); // 将新书放在程序表最初面
booklist.setUsedSize(size+1); // 程序表放了新书之后,长度加 1
}
}
// 借阅
public class BorrowOperation implements IOperation{
@Override
public void work(BookList booklist) {System.out.println("借阅书籍");
Scanner sc = new Scanner(System.in);
System.out.println("请输出书名");
String name = sc.nextLine(); //name 为所要借阅书名
for (int i = 0; i < booklist.getUsedSize(); i++) {
// 通过 booklist 下标遍历每一本书
Book book = booklist.getBooks(i);
if(book.getName().equals(name)){
// 如果为 true,阐明要借阅的书存在,咱们须要做的是批改书的借阅状态
book.setBorrowed(true); // 为 true 示意书曾经结出
return ;
}
}
System.out.println("十分道歉,本馆没有您要借阅的书!"); //
}
}
// 删除
public class DelOperation implements IOperation{
@Override
public void work(BookList booklist) {System.out.println("删除书籍");
Scanner sc = new Scanner(System.in);
System.out.println("请输出书名");
String name = sc.nextLine(); //name 为所要删除的书名
int i = 0;
for (; i < booklist.getUsedSize(); i++) {Book book = booklist.getBooks(i);
if(book.getName().equals(name)){break;}
}
if(i >= booklist.getUsedSize()){System.out.println("没有要删除的这本书!");
return ;
}
// 此时 i 为所要删除书的下标
for (int j = i; j < booklist.getUsedSize()-1; j++) {Book book = booklist.getBooks(j+1); // 取得 j + 1 地位的书
booklist.setBooks(j,book); // 将 j + 1 地位的书给 j 地位
}
int size = booklist.getUsedSize(); // 取得程序表长度
booklist.setUsedSize(size-1); // 删除书后,长度减去 1
System.out.println("书已被删除!");
}
}
// 展现
public class DisplayOperation implements IOperation{
@Override
public void work(BookList booklist) {System.out.println("展现书籍");
for (int i = 0; i < booklist.getUsedSize(); i++) {Book book = booklist.getBooks(i);
System.out.println(book);
}
}
}
// 查找
public class FindOperation implements IOperation{
@Override
public void work(BookList booklist) {System.out.println("查找书籍");
Scanner sc = new Scanner(System.in);
System.out.println("请输出书名");
String name = sc.nextLine(); //name 为所要查找书名
for (int i = 0; i < booklist.getUsedSize(); i++) {
// 通过 booklist 下标遍历每一本书
Book book = booklist.getBooks(i);
if(book.getName().equals(name)){System.out.println("该书存在!");
System.out.println(book); // 间接打印书的信息,toString 办法已被重写
return ;
}
}
System.out.println("没有这本书!");
}
}
// 偿还
public class ReturnOperation implements IOperation{
@Override
public void work(BookList booklist) {System.out.println("偿还书籍");
Scanner sc = new Scanner(System.in);
System.out.println("请输出书名");
String name = sc.nextLine(); //name 为所要偿还的书名
for (int i = 0; i < booklist.getUsedSize(); i++) {Book book = booklist.getBooks(i);
if(book.getName().equals(name)){book.setBorrowed(false);
System.out.println(book); // 间接打印书的信息,toString 办法已被重写
return ;
}
}
System.out.println("没有你要偿还的这本书!");
}
}
// 退出
public class ExitOperation implements IOperation{
@Override
public void work(BookList booklist) {System.out.println("退出零碎");
System.exit(1); // 示意退出零碎
}
}
// 总接口
public interface IOperation {void work(BookList booklist);
}
用户相干类
<mark style=”box-sizing: border-box; outline: 0px; background-color: rgb(248, 248, 64); color: rgb(0, 0, 0); overflow-wrap: break-word;”> 用户类 </mark>
package user;
import book.BookList;
import operation.IOperation;
/**
* Created with IntelliJ IDEA
* Details about unstoppable_t:
* User: Administrator
* Date: 2021 -01-19
* Time: 16:55
*/
abstract public class User {
public String name;
public IOperation[] operations;
public User(String name){this.name = name;}
/*
新建 menu 办法,了解为用户菜单
因为 SpecialPerson 和 OrdinaryPerson 继承了 User,所以让两个子类重写 menu 办法,二者的菜单展现不统一
此时 menu 能够没有具体实现,因此将它设计为形象办法,因而 User 类成为抽象类
*/
abstract public int menu();
//operations 中寄存的是哪些操作方法,得看子类
public void doOperation(int choice, BookList bookList){this.operations[choice].work(bookList);
}
}
<mark style=”box-sizing: border-box; outline: 0px; background-color: rgb(248, 248, 64); color: rgb(0, 0, 0); overflow-wrap: break-word;”> 管理员 </mark>
package user;
import operation.*;
import java.util.Scanner;
/**
* Created with IntelliJ IDEA
* Details about unstoppable_t:
* User: Administrator
* Date: 2021 -01-19
* Time: 16:56
* 管理员
*/
public class SpecialPerson extends User{
// 构造方法
public SpecialPerson(String name){super(name);
this.operations = new IOperation[]{new ExitOperation(), // 0 退出零碎
new FindOperation(),
new AddOperation(),
new DelOperation(),
new DisplayOperation()};
}
/*
重写父类 User 的 menu 办法
menu 作用:返回你要执行的操作
*/
@Override
public int menu() {System.out.println("管理员菜单!");
System.out.println("=================================");
System.out.println("hello" + this.name + "赤诚欢送应用本校图书馆管理系统!");
System.out.println("1. 查找图书");
System.out.println("2. 新增图书");
System.out.println("3. 删除图书");
System.out.println("4. 显示所有图书");
System.out.println("0. 退出零碎");
System.out.println("================================");
System.out.println("请依照提醒抉择相应操作:");
Scanner sc = new Scanner(System.in);
int choice = sc.nextInt();
return choice;
}
}
<mark style=”box-sizing: border-box; outline: 0px; background-color: rgb(248, 248, 64); color: rgb(0, 0, 0); overflow-wrap: break-word;”> 普通用户 </mark>
package user;
import operation.*;
import java.util.Scanner;
/**
* Created with IntelliJ IDEA
* Details about unstoppable_t:
* User: Administrator
* Date: 2021 -01-19
* Time: 16:57
* 普通用户
*/
public class OrdinaryPerson extends User{
// 构造方法
public OrdinaryPerson(String name){super(name);
this.operations = new IOperation[]{new ExitOperation(), // 0 退出零碎
new FindOperation(),
new BorrowOperation(),
new ReturnOperation()};
}
// 重写父类 User 的 menu 办法
@Override
public int menu() {System.out.println("普通用户菜单!");
System.out.println("=================================");
System.out.println("hello" + this.name + "赤诚欢送应用本校图书馆管理系统!");
System.out.println("1. 查找图书");
System.out.println("2. 借阅图书");
System.out.println("3. 偿还图书");
System.out.println("0. 退出零碎");
System.out.println("================================");
System.out.println("请依照提醒抉择相应操作:");
Scanner sc = new Scanner(System.in);
int choice = sc.nextInt();
return choice;
}
}
主函数程序
import book.BookList;
import user.OrdinaryPerson;
import user.SpecialPerson;
import user.User;
import java.util.Scanner;
/**
* Created with IntelliJ IDEA
* Details about unstoppable_t:
* User: Administrator
* Date: 2021 -01-19
* Time: 16:30
*/
public class TrqTest {
//login(登录)办法返回用户实例,类型为 User
public static User login(){Scanner sc = new Scanner(System.in);
System.out.println("请输出你的姓名:");
String name = sc.nextLine();
System.out.println("请输出你的身份 > 1: 管理员 0: 普通用户");
int number = sc.nextInt();
if(number == 1){return new SpecialPerson(name);
}else{return new OrdinaryPerson(name);
}
}
public static void main(String[] args) {BookList bookList = new BookList();
// 登录
User user = login(); // 父类援用指向子类实例(向上转型)while(true) {//user.menu() 调用哪个 menu 办法,依据登录身份决定
int choice = user.menu();
// 此 doOperation 办法是以后 user 本人的办法
//choice 抉择以后用户 operations 数组中的相应的类,该类产生的对象调用本人的 work 办法
user.doOperation(choice, bookList);
}
}
}
运行一下看看具体怎么样吧
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