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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