目录
图书管理系统
简单的示意图:
分析:
各个类的实现
1.Book类
2.BookList类
3.因为Operation包中各个操作都需要用到book,所以创建一个接口IOperation
4.User类
5.Admin类
6.Normal类
7.Main类
8.实现DisplayOperation
9.实现FindOperation
10.实现AddOperation
11.实现BorrowOperation
12.实现ReturnOperation
13.实现DelOperation
14.ExitOperation
运行结果图:
图书管理系统
简单的示意图:
分析:
此时分为3部分:
一.书的内容和存取书
二.用户登录,分为管理员和普通用户
三.书相关操作
分别可以创建三个包 package bookpackage operationpackage user
book包中可以用Book类来表示一本书BookList类来表示N本书
user包中可以使用User类来表示用户,其中User又有 普通用户 可以用NomalUser类来表示 管理员用Admin类来表示
Operation包中分别用
AddOperation类来表示增添图书
DelOperation类来表示删除图书
FindOperation类来表示查找图书
DisplayOperation类来表示显示图书
BorrowOperation类来表示显示图书
ReturnOperation类来表示归还图书
ExitOperation类来表示退出图书
各个类的实现
1.Book类
package book;public class Book {private String name ;//书的书名private String author;//书的作者private int price;//书的价格private String type;//书的类型private boolean isBorrowed;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 isBorrowed() {return isBorrowed;}public void setBorrowed(boolean borrowed) {isBorrowed = borrowed;}@Overridepublic String toString() {return "Book{" +"name='" + name + '\'' +", author='" + author + '\'' +", price=" + price +", type='" + type + '\'' +", " +((isBorrowed==true)?"被借出":"未被借出")+'}';}}
2.BookList类
package book;public class BookList {private Book[] books = new Book[100];//用顺序表的方式存书private int usedSize;public BookList(){//给3本书在图书管理系统里books[0] = new Book("Java SE","博哥",2000,"专业知识");books[1] = new Book("Java EE","大博哥",3000,"专业知识");books[2] = new Book("数据结构","博哥哥",4000,"理论知识");usedSize=3;}public Book getBook(int pos) {return this.books[pos];}public void setBooks(int pos,Book book) {this.books[pos] = book;}public int getUsedSize() {return usedSize;}public void setUsedSize(int usedSize) {this.usedSize = usedSize;}}
3.因为Operation包中各个操作都需要用到book,所以创建一个接口IOperation
package Operation;import book.BookList;import java.util.Scanner;public interface IOperation {public void work(BookList bookList);Scanner sc = new Scanner(System.in);}
4.User类
package user;import Operation.IOperation;import book.BookList;abstract public class User {protected String name ;//用户名protected IOperation[] iOperations;//对书的操作public User(String name){this.name = name;}abstract public int menu();public void doOperation(int choice, BookList bookList) {this.iOperations[choice].work(bookList);}}
5.Admin类
package user;import Operation.*;import book.BookList;import java.util.Scanner;public class Admin extends User {public Admin(String name) {super(name);this.iOperations = new IOperation[]{new ExitOperation(),//下标为0new FindOperation(),//下标为1new AddOperation(),//下标为2new DelOperation(),//下标为3new DisplayOperation()//下标为4};}@Overridepublic int menu() {System.out.println("======================================");System.out.println("hello "+this.name+" 欢迎来到图书馆里系统");System.out.println("1.查阅图书");System.out.println("2.添加图书");System.out.println("3.删除图书");System.out.println("4.显示图书");System.out.println("0.退出系统");System.out.println("======================================");Scanner sc = new Scanner(System.in);int choice = sc.nextInt();return choice;}}
6.Normal类
package user;import Operation.*;import java.util.Scanner;public class NormalUser extends User{public NormalUser(String name) {super(name);this.iOperations = new IOperation[]{new ExitOperation(),//下标为0new FindOperation(),//下标为1new BorrowOperation(),//下标为2new ReturnOperation()//下标为3};}@Overridepublic int menu() {System.out.println("======================================");System.out.println("hello "+this.name+" 欢迎来到图书馆里系统");System.out.println("1.查阅图书");System.out.println("2.借出图书");System.out.println("3.归还图书");System.out.println("0.退出系统");System.out.println("======================================");Scanner sc = new Scanner(System.in);int choice = sc.nextInt();return choice;}}
7.Main类
import book.BookList;import user.Admin;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 sc = new Scanner(System.in);String name = sc.nextLine();System.out.println("请选择你的身份: 1. 管理员 2. 普通用户");int choice = sc.nextInt();if(choice==1){return new Admin(name);}else{return new NormalUser(name);}}public static void main(String[] args) {BookList bookList = new BookList();User user = login();//返回的是子类对象,父类引用 引用 子类对象 发生向上转型while(true) {int choice = user.menu();//父类引用调用了同名的覆盖方法 此时发生动态绑定user.doOperation(choice,bookList);}}}
8.实现DisplayOperation
package Operation;import book.Book;import book.BookList;public class DisplayOperation implements IOperation{@Overridepublic void work(BookList bookList) {System.out.println("显示图书");for (int i = 0; i < bookList.getUsedSize(); i++) {Book book = bookList.getBook(i);System.out.println(book);}}}
9.实现FindOperation
package Operation;import book.Book;import book.BookList;public class FindOperation implements IOperation{@Overridepublic void work(BookList bookList) {System.out.println("查找图书");System.out.println("请输入你要查找的图书的书名:");String name = sc.nextLine();for (int i = 0; i < bookList.getUsedSize(); i++) {Book book = bookList.getBook(i);if(book.getName().equals(name)){System.out.println("找到了这本书!");System.out.println(book);//找到了这本书直接returnreturn;}}//循环结束 没有找到书System.out.println("没有这本书!");}}
10.实现AddOperation
package Operation;import book.Book;import book.BookList;public class AddOperation implements IOperation{@Overridepublic void work(BookList bookList) {System.out.println("添加图书! ");System.out.println("请输入你要添加图书的书名:");String name = sc.next();System.out.println("请输入你要添加图书的作者:");String author = sc.next();System.out.println("请输入你要添加图书的价格:");int price = sc.nextInt();System.out.println("请输入你要添加图书的类型:");String type = sc.next();Book book = new Book(name,author,price,type);bookList.setBooks(bookList.getUsedSize(), book);bookList.setUsedSize(bookList.getUsedSize()+1);//usedSize要加1System.out.println("添加成功! ");}}
11.实现BorrowOperation
package Operation;import book.Book;import book.BookList;public class BorrowOperation implements IOperation{@Overridepublic void work(BookList bookList) {System.out.println("借出图书");System.out.println("请输入你要借的书名:");String name = sc.nextLine();for (int i = 0; i < bookList.getUsedSize(); i++) {Book book = bookList.getBook(i);if(book.getName().equals(name)){book.setBorrowed(true);System.out.println("借书成功");return;}}System.out.println("没有你要借的书!");}}
12.实现ReturnOperation
package Operation;import book.Book;import book.BookList;public class ReturnOperation implements IOperation{@Overridepublic void work(BookList bookList) {System.out.println("归还图书");System.out.println("请输入你要归还的图书:");String name = sc.nextLine();for (int i = 0; i < bookList.getUsedSize(); i++) {Book book = bookList.getBook(i);if(book.getName().equals(name)){book.setBorrowed(true);System.out.println("归还成功!");return;}}System.out.println("没有你要归还的书籍");}}
13.实现DelOperation
package Operation;import book.Book;import book.BookList;public class DelOperation implements IOperation{@Overridepublic void work(BookList bookList) {System.out.println("删除图书");System.out.println("请输入你要删除的图书的书名:");String name = sc.nextLine();int pos = -1;for (int i = 0; i < bookList.getUsedSize(); i++) {Book book = bookList.getBook(i);if (book.getName().equals(name)){pos = i;break;//有相同的书就返回i的下标}}if(pos == -1){//当pos没有改变时,直接返回System.out.println("没有你要删除的书籍");return;}//将pos位置删除,从后往前交换for (int i = pos; i < bookList.getUsedSize(); i++) {Book book = bookList.getBook(i+1);bookList.setBooks(i,book);}bookList.setUsedSize(bookList.getUsedSize()-1);//usedSize要-1System.out.println("删除成功!");}}
14.ExitOperation
package Operation;import book.BookList;public class ExitOperation implements IOperation{@Overridepublic void work(BookList bookList) {System.out.println("退出系统");System.exit(0);}}
