类和对象实现简单的图书管理

package com.fnd.book.entity;

import com.fnd.book.biz.BookBiz;
import com.fnd.book.entity.ex.EX;
public class User {
public String name;
public String password;

public String getName() {
	return name;
}

public void setName(String name) {
	this.name = name;
}

public String getPassword() {
	return password;
}

public void setPassword(String password) {
	this.password = password;
}

/**
 * 图书入库
 * @param bookId
 * @param num
 */
public void in(int bookId,int num){
	BookBiz bookBiz=new BookBiz();
	bookBiz.inBook(bookId, num);
}

/**
 * 图书出库
 * @param bookId
 * @param num
 */
public void out(int bookId, int num) {
	BookBiz bookBiz=new BookBiz();
	bookBiz.outBook(bookId, num);
	
}

/**
 * 新增图书
 */
public void save(Book book) {
	BookBiz bookBiz=new BookBiz();
	bookBiz.saveBook(book);
	System.out.println("新增图书成功!");
}	

/**
 * 买赠品 
 */
public EX buyEx(int exCode) {
	BookBiz bookBiz=new BookBiz();
	return bookBiz.buyEx(exCode);
}
/**
 * 购买图书
 */
public Book buy(int bookId, int num) {
	BookBiz bookBiz=new BookBiz();
	return bookBiz.buyBook(bookId,num);
}

/**
 * 结账
 */
public void checkout(Book book) {
	BookBiz bookBiz=new BookBiz();
	bookBiz.checkout(book);	
}
/**
 * 库存查询
 */
public void query(){
	BookBiz bookBiz = new BookBiz();
	bookBiz.query();
}

}
package com.fnd.book.entity;
import com.fnd.book.entity.ex.EX;
public class Book {
public int id;
public String name;
public String author;
public String pub_date;
public int store;
public double price;
public int num;
public EX ex;
//不添加构造方法:每一个属性的赋值由用户一项一项输入

	/**
	 * 计算价钱
	 * @return 总价
	 */
public double cost() {
	//显示书名和单价及购买数量
	System.out.println("购买的图书:"+name+"价格:"+price+"数量:"+num);
	//先输出不购买赠品情况下的价格
	System.out.println("不购卖赠品的总价格:"+(price*num));
	//还要考虑购买赠品的情况:加赠品价格
	return price*num;
	}	
public Book(int id, String name,String author, String pub_date, double price, int store) {
	// TODO Auto-generated constructor stub
	this.id=id;
	this.name=name;
	this.author=author;
	this.pub_date=pub_date;
	this.store=store;
	this.price=price;
}
public Book() {
	// TODO Auto-generated constructor stub
}
public String getName() {
	return name;
}
public void setName(String name) {
	this.name = name;
}
public EX getEx() {
	return ex;
}
public void setEx(EX ex) {
	this.ex = ex;
}
//static final EX;
public int getId() {
	return id;
}
public void setId(int id) {
	this.id = id;
}

public String getPub_date() {
	return pub_date;
}
public void setPub_date(String pub_date) {
	this.pub_date = pub_date;
}
public int getStore() {
	return store;
}
public void setStore(int store) {
	this.store = store;
}
public double getPrice() {
	return price;
}
public void setPrice(double price) {
	this.price = price;
}
public int getNum() {
	return num;
}
public void setNum(int num) {
	this.num = num;
}
public String getAuthor() {
	return author;
}
public void setAuthor(String author) {
	this.author = author;
}

}
//CD,Pen与Bag相同
package com.fnd.book.entity.ex;
public class Bag extends EX {
public Bag() {
setEx_name("BAG");
setPrice(2.7);
}
}
//附赠品类
package com.fnd.book.entity.ex;

public abstract class EX {
private String ex_name;
private double price;
public String getEx_name() {
return ex_name;
}
public void setEx_name(String ex_name) {
this.ex_name = ex_name;
}
public double getPrice() {
return price;
}
public void setPrice(double price) {
this.price = price;
}

/**
 * 附赠品价格计算
 * @return
 */
public double cost() {
	//输出附赠品的名称和价格,返回价格	
	System.out.println("购买的附赠品名称是:"+ex_name+"价格是:"+price);
	return price;
}

}
package com.fnd.book.entity.ex;

public class ExFactory {
/**
* 创建附赠品
* @param id 用户选择赠品的编号
* @return 对应的赠品对象
*/
public static EX create(int id) {
switch (id) {
case 1:
return new CD();
case 2:
return new Bag();
case 3:
return new Pen();
default:
return null;
}
}
}
package com.fnd.book.biz;

import com.fnd.book.entity.Book;
import com.fnd.book.entity.ex.EX;
import com.fnd.book.entity.ex.ExFactory;

public class BookBiz {
// 对象数组
static Book[] books = new Book[30];
Book book = new Book();
/**
* 初始化5本圖書信息
/
public static void makeData() {
// 创建5本书对象,添加至books数组
//构造方法初始化
Book book1 = new Book(10001, "白夜行", "冬夜圭吾", "2010-12-12", 11.0, 11);
Book book2 = new Book(10002, "白夜行", "冬夜圭吾", "2010-12-12", 11.0, 11);
Book book3 = new Book(10003, "白夜行", "冬夜圭吾", "2010-12-12", 11.0, 11);
Book book4 = new Book(10004, "白夜行", "冬夜圭吾", "2010-12-12", 11.0, 11);
Book book5 = new Book(10005, "白夜行", "冬夜圭吾", "2010-12-12", 11.0, 11);
//setter初始化
/
book1.setId(10001);
book1.setName("白夜行");
book1.setAuthor("张华");
book1.setPub_date("2010-12-12");
book1.setPrice(12.4);
book1.setStore(20);/
// 对象放入对象数组
books[0] = book1;
books[1] = book2;
books[2] = book3;
books[3] = book4;
books[4] = book5;
/
// 遍历输出图书信息
for (int i = 0; i < books.length; i++) {
Book b = books[i];
// System.out.println(b.getId()+" "+b.getName()+" "+b.getAuther()+" "+b.getPub_date()+" "+b.getPrice()+" "+b.getStore());
}*/
}
/**
* 查询图书是否存在:不管是新增、入库、出库、结账都需先判断
* @param id 编号
* @return Book对象
/
public Book findBookById(int id){
for (int i = 0; i < books.length; i++) {
if (books[i]!=null) {
if(books[i].getId()id){
return books[i];
}
}
}
return null;//for循环结束还未返回,表示未找到
}
/
*
* 图书入库
*/
public void inBook(int bookId, int num) {
//先查找是否存在
Book book = findBookById(bookId);
//不存在就返回,存在则增加book[i]的库存量
if (booknull) {
System.out.println("要入库的图书不存在");
}else {
//存在增加库存
book.setStore(book.getStore()+num);
System.out.println("图书入库成功!");
}
}

/**
 * 图书出库
 */
public void outBook(int bookId,int num) {
	//先查找是否存在
	Book book =findBookById(bookId);
	//如找到,减少该book[i]的库存量
	if (book==null) {
		System.out.println("要出库的图书不存在");
	}else{
		//存在图书,可以出库,判断库存和出库数量
		if (book.getStore()>=num) {
			//可以出库
			book.setStore(book.getStore()-num);
			System.out.println("图书出库成功!");
		}else{
			//不合法
			System.out.println("库存不足");
		}
	}

}
/**
 * 新增图书
 * @param book
 */
public void saveBook(Book book) {
	//方法1
	/*for (int i = 0; i < books.length; i++) {
		if (books[i]==null) {
			books[i+1]=book;
			book.setId(books[i-1].getId()+1);
			break;
		}
	}*/
	
	//方法2
	//为新增输入编号,为上一本书编号加1
	int index=-1;
	for (int i = 0; i < books.length; i++) {
		if (books[i]==null) {
			index=i;
			break;
		}
	}
	//取最后一本书的id
	int id =books[index-1].getId();
	book.setId(id+1);
	//把新增对象添加到数组
	books[index]=book;
}
/**
 * 查询图书
 */
public void query() {
	// 遍历输出图书信息
	//方法1
	/*System.out.println("书号	" + "书名	" + "作者	" + "发布日期	"
			+ "价格	" + "库存");
	for (Book b : books) {
		if (b != null) {
			System.out.println(b.getId() + "	" + b.getName() + "	" + b.getAuthor() + "	" + b.getPub_date() + "	"
					+ b.getPrice() + "	" + b.getStore());
		}
	}*/
	//方法2
	System.out.println("序号	书名	作者	出版日期		价格	库存");
	//循环Books数组
	for (int i = 0; i < books.length; i++) {
		if (books[i]!=null) {
			System.out.println(books[i].getId()+"	"+books[i].getName()+"	"+books[i].getAuthor()+"	"+books[i].getPub_date()+"	"+books[i].getPrice()+"	"+books[i].getStore());
		}
	}
}

/**
 * 购买附赠品
 * @return 附赠品
 */
public EX buyEx(int exCode) {
	return ExFactory.create(exCode);//调用工厂里的方法,根据用户选择的数字生成对应的附赠品
}

/**
 * 结账
 */
public void checkout(Book book){
	double totalPrice;
	//减少库存数量
	book.setStore(book.getStore()-book.getNum());
	//输出总价格
	if (book.getEx()!=null) {
		//购买的有附赠品
		totalPrice = book.cost()+book.getEx().getPrice();
		System.out.println("购买附赠品后的总价格="+totalPrice);
	}
}
/**
 * 购买图书
 * @return 被购买书的对象
 */
public Book buyBook(int bookId, int num) {
	// 查找到图书
	Book book=findBookById(bookId);
	if (book==null) {
		System.out.println("要购买的图书不存在");
	}else {
		//找到购买图书,蛇者购买book[i]的购买数量
		if (num<book.getStore()) {
			book.setNum(num);
		}else{
			System.out.println("库存不足");
		}	
	}
	return book;
}

}
package com.fnd.book;

import java.util.Scanner;

import com.fnd.book.biz.BookBiz;
import com.fnd.book.entity.*;
import com.fnd.book.entity.ex.EX;
public class TestBook {
Scanner input = new Scanner(System.in);
User user = new User();
public static void main(String[] args) {

	BookBiz.makeData();
	TestBook test = new TestBook();
	System.out.println("欢迎使用图书书店");
	//登陆
	test.accreditRole();
}

private void accreditRole() {
	// TODO Auto-generated method stub
	System.out.print("请输入用户名:");
	String username = input.next();
	System.out.print("请输入密码:");
	String pwd = input.next();
	//给属性赋值
	user.setName(username);
	user.setPassword(pwd);
	if (username.equals("admin")&&pwd.equals("admin")) {
		doStoreMgr(user);//管理员
	}else {
		doCustomer(user);//用户
	}
}

/**
 * 顾客的操作
 */
private void doCustomer(User user) {
	System.out.println("*****欢迎光临图书系统*****");
	System.out.println("请选择进行的操作:1.查看图书   2.结账   3.退出");
	int choice=input.nextInt();
	switch (choice) {
	case 1:   
		//查询
		user.query();
		doCustomer(user);
		break;
	case 2:
		//购买
		Book book = null;
		System.out.println("请输入想要购买的图书信息:");
		System.out.println("请输入图书ID:");
		int id = input.nextInt();
		System.out.println("请输入购买数量:");
		int num = input.nextInt();
		book = user.buy(id, num);
		if (book != null) {
			while (true) {
				System.out.print("1.CD 27.50元      2.包装  2.70元       3.钢笔 10元     4.不需要
请输入需要购买的附赠品:");
				int exCode = input.nextInt();
				if (exCode >= 1 && exCode <= 4) {
					EX ex = user.buyEx(exCode);
					book.setEx(ex);//将赠品对象传递为book对象,计算总价
					user.checkout(book);
					break;
				} 
			}
		}
		doCustomer(user);
		break;
	case 3:
		//退出
		System.out.println("谢谢使用!");
		return;
	default:
		break;
	}
}

/**
 * 库存管理员操作
 */	
private void doStoreMgr(User user) {
	System.out.println("欢迎登陆库存管理系统");
	System.out.print("请选择进行的操作:");
	//方法1
	/*String inits[] = { "1.图书入库", "2.图书出库", "3.查询全部图书", "4.新增图书", "5.退出" };
	for (String string : inits) {
		System.out.print(string);
	}
	System.out.println();*/
	//方法2
	System.out.println("请选择进行的操作:1.图书入库     2.图书出库     3.查询全部图书     4.新增图书     5.退出");
	int choice=0;
	choice = input.nextInt();
	int num;
	switch(choice){
	case 1:
		//入库
		System.out.println("输入入库的图书ID:");
		int bookId=input.nextInt();
		System.out.println("输入入库的数量");
		num=input.nextInt();
		user.in(bookId, num);
		doStoreMgr(user);  //这样可以实现循环
		break;
	case 2:
		//出库
		System.out.print("请输入ID:");
		int id = input.nextInt();
		System.out.print("请输入出库的数量:");
		num = input.nextInt();
		user.out(id, num);// 出库
		doStoreMgr(user);
		break;
	case 3:
		//查询
		user.query();
		doStoreMgr(user);  //这样可以实现循环
		break;
	case 4:
		//新增
		Book book = new Book();
		System.out.print("请输入图书信息");
		System.out.print("请输入书名:");
		String name = input.next();
		System.out.print("请输入作者:");
		String author = input.next();
		System.out.print("请输入出版时间:");
		String pub_date = input.next();
		System.out.print("请输入价格:");
		double price = input.nextDouble();
		System.out.print("请输入数量:");
		int store = input.nextInt();
		book.setName(name);
		book.setAuthor(author);
		book.setPub_date(pub_date);
		book.setPrice(price);
		book.setStore(store);
		user.save(book);
		doStoreMgr(user);
		break;
	case 5:
		//退出
		System.out.println("谢谢使用");
		return;
	default:
		System.out.println("输入有误");
		break;
	}
}

}

原文地址:https://www.cnblogs.com/rainsnow/p/12200223.html