需求
1、简单的登录
2、管理端
整理书籍(该功能为可扩展功能)
查阅书籍
增加书籍
删除书籍
打印书籍列表
退出
3、用户端
查询书籍
借阅书籍
归还书籍
退出
类的设计
大致先分为三个包:book , user , operation,后根据需求设计各个包中的类。
代码
针对每个类完善内容:
Book
package book;
public class Book {
private String name;//书名
private String author;//作者
private int price;//价格
private String type;//类型
private boolean statue;//状态,默认false
//构造
public Book(String name, String author, int price, String type) {
this.name = name;
this.author = author;
this.price = price;
this.type = type;
}
//getter/setter
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 isStatue() {
return statue;
}
public void setStatue(boolean statue) {
this.statue = statue;
}
//toString
@Override
public String toString() {
return "Book{" +
"name='" + name + '\'' +
", author='" + author + '\'' +
", price=" + price +
", type='" + type + '\'' +
((statue)?",借出":",未借出")+
'}';
}
}
BookList
package book;
public class BookList {
private Book[] books;//相当于书架
private int usedSize;//书架上书的个数
//构造
public BookList(){
this.books=new Book[10];
books[0]=new Book("book1","Mary",72,"科幻");
books[1]=new Book("book2","Bob",53,"历史");
books[2]=new Book("book3","Alice",33,"悬疑");
this.usedSize=3;
}
//尾插法
public void setBooks(int pos,Book book){
this.books[pos]=book;
}
public Book getBook(int pos){
return this.books[pos];
}
public int getUsedSize() {
return usedSize;
}
public void setUsedSize(int usedSize) {
this.usedSize = usedSize;
}
}
AddOperation
package operation;
import book.Book;
import book.BookList;
import java.util.Scanner;
public class AddOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("添加:");
Scanner sc=new Scanner(System.in);
System.out.println("请输入图书的名字");
String name=sc.nextLine();
System.out.println("请输入图书的作者");
String author=sc.nextLine();
System.out.println("请输入图书的价格");
int price=sc.nextInt();
System.out.println("请输入图书的类型");
String type=sc.next();
Book book=new Book(name,author,price,type);
int currentSize=bookList.getUsedSize();
bookList.setBooks(currentSize,book);
bookList.setUsedSize(currentSize+1);
}
}
DelOperation
package operation;
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");
Scanner sc=new Scanner(System.in);
System.out.print("请输入要删除的书名:");
String name=sc.nextLine();
int i;
for ( i = 0; i <bookList.getUsedSize() ; i++) {
Book book=bookList.getBook(i);
if(book.getName().equals(name)){
break;
}
}
if(i>=bookList.getUsedSize()) {
System.out.println("查无此书!");
return;
}
int pos=i;
for (int j = pos; j < bookList.getUsedSize()-1; j++) {
Book book=bookList.getBook(j+1);
bookList.setBooks(j,book);
}
int currentSize= bookList.getUsedSize();
bookList.setUsedSize(currentSize-1);
System.out.println("删除完毕!");
}
}
FindOperation
package operation;
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:");
Scanner sc=new Scanner(System.in);
System.out.println("请输入查找图书的名字");
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!");
System.out.println(book);
return;
}
}
System.out.println("查无此书!");
}
}
ReturnOperation
import book.Book;
import book.BookList;
import user.AdminUser;
import user.NormalUser;
import user.User;
import java.util.Scanner;
public class Main {
public static User login(){
Scanner sc=new Scanner(System.in);
System.out.print("请输入你的姓名:");
String name=sc.nextLine();
System.out.println("请输入你的身份:0:普通用户,1:管理员");
int choice=sc.nextInt();
if(choice==1){
return new AdminUser(name);
}else{
return new NormalUser(name);
}
}
public static void main(String[] args) {
BookList bookList=new BookList();
//1.登录 user 会引用一个对象 管理员 或 普通用户
User user=login();
while(true) {//循环,多次输入
// 会调用 user引用的对象的menu(菜单),并放回对应的选择(要执行的操作)
int choice = user.menu();
//2.拿choice去调用对应类的work方法
// work 方法有很多,菜单中的每个操作都有
//具体调用谁的 交给doOperation
user.doOperation(choice, bookList);
}
}
}
DisplayOperation
package operation;
import book.Book;
import book.BookList;
public class DisplayOperation implements IOperation {
@Override
public void work(BookList bookList) {
System.out.println("显示所有图书:");
for (int i = 0; i <bookList.getUsedSize() ; i++) {
Book book=bookList.getBook(i);
System.out.println(book);
}
}
}
BorrowOperation
package operation;
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");
Scanner sc=new Scanner(System.in);
System.out.print("请输入要借阅的书名:");
String name=sc.nextLine();
for (int i = 0; i <bookList.getUsedSize() ; i++) {
Book book=bookList.getBook(i);
if(book.getName().equals(name)){
//说明有这本书
book.setStatue(true);
return;
}
}
System.out.println("查无此书!");
}
}
ReturnOperation
package operation;
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:");
Scanner sc=new Scanner(System.in);
System.out.println("请输入归还图书的名字");
String name=sc.nextLine();
for (int i = 0; i <bookList.getUsedSize() ; i++) {
Book book=bookList.getBook(i);
if(book.getName().equals(name)){
book.setStatue(false);
System.out.println(book);
return;
}
}
System.out.println("查无此书!");
}
}
ExitOperation
package operation;
import book.BookList;
public class ExitOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("退出系统!");
System.exit(1);
}
}
AdminUser
package user;
import operation.*;
import java.util.Scanner;
//管理员
public class AdminUser extends User {
public AdminUser(String name) {
super(name);
this.operations=new IOperation[]{
new ExitOperation(),
//注意下标顺序,与菜单对应,0表示退出
new FindOperation(),
new AddOperation(),
new DelOperation(),
new DisplayOperation()
};
}
//返回你要执行的对应的操作
@Override
public int menu() {//返回的是输入的菜单中的选项,所以int
Scanner sc=new Scanner(System.in);
System.out.println("======================");
System.out.println("hello,"+this.name);
System.out.println("1.查找");
System.out.println("2.增加");
System.out.println("3.删除");
System.out.println("4.显示");
System.out.println("0.退出系统");
System.out.println("======================");
int choice=sc.nextInt();
return choice;
}
}
NormalUser
package user;
import operation.*;
import java.util.Scanner;
//普通用户
public class NormalUser extends User {
public NormalUser(String name) {
super(name);
this.operations=new IOperation[]{
new ExitOperation(),
//注意下标顺序,0表示退出
new FindOperation(),
new BorrowOperation(),
new ReturnOperation(),
};
}
//返回你要执行的对应的操作
@Override
public int menu() {
Scanner sc=new Scanner(System.in);
System.out.println("======================");
System.out.println("hello,"+this.name);
System.out.println("1.查找");
System.out.println("2.借阅");
System.out.println("3.归还");
System.out.println("0.退出系统");
System.out.println("======================");
int choice=sc.nextInt();
return choice;
}
}
Main
import book.Book;
import book.BookList;
import user.AdminUser;
import user.NormalUser;
import user.User;
import java.util.Scanner;
public class Main {
public static User login(){
Scanner sc=new Scanner(System.in);
System.out.print("请输入你的姓名:");
String name=sc.nextLine();
System.out.println("请输入你的身份:0:普通用户,1:管理员");
int choice=sc.nextInt();
if(choice==1){
return new AdminUser(name);
}else{
return new NormalUser(name);
}
}
public static void main(String[] args) {
BookList bookList=new BookList();
//1.登录 user 会引用一个对象 管理员 或 普通用户
User user=login();
while(true) {//循环,多次输入
// 会调用 user引用的对象的menu(菜单),并放回对应的选择(要执行的操作)
int choice = user.menu();
//2.拿choice去调用对应类的work方法
// work 方法有很多,菜单中的每个操作都有
//具体调用谁的 交给doOperation
user.doOperation(choice, bookList);
}
}
}
运行结果:
普通人身份:
管理员身份: