JAVA程序设计(14.1)----- 图书馆管理系统 初步设计 内部功能篇

Posted 2020-09-28 jzdwajue

首先绘制思维导图。右下的user临时无论先……

先做Book。抽象化属性，核心功能。

然后是绘制BookManager的主要功能

然后直接导出到Eclipse进行改动调整，完毕功能的内部结构例如以下：

package com.lovo.BookManager;

import java.sql.Date;
import java.text.SimpleDateFormat;

/**
 * @author Abe
 * @version 1.0
 * @created 05-十一月-2011 15:58:35
 */
public class Book implements Comparable<Book>{
	final long THE_DAY = 1000 * 60 * 60 * 24;
	private String name;
	private String isbn;
	private double price;
	private boolean lended;
	private int counter;
	private long lendDate;

	/**
	 * 构造器
	 */
	public Book(String isbn, String name , double price){
		this.isbn = isbn ;
		this.name = name ;
		this.price = price;
		this.counter = (int)(Math.random()* 50);
	}

	/**
	 * 借出
	 * @return
	 */
	public boolean lendOut() {
		if (!lended) {
			lended = true;
			counter++;
			lendDate = System.currentTimeMillis();
			return true;
		}
		return false;
	}

	/**
	 * 归还
	 * @return
	 */
	public double returnBack() {
		if (lended) {
			lended = false;
			long currentTime = System.currentTimeMillis();
			int days = (int) Math.ceil((currentTime - lendDate) / THE_DAY);
			lendDate = 0;
			return days * price;
		}
		return 0;
	}

	public String getName() {
		return name;
	}

	public String getIsbn() {
		return isbn;
	}

	public double getPrice() {
		return price;
	}

	public boolean isLended() {
		return lended;
	}

	public int getCounter() {
		return counter;
	}

	/**
	 * 出借日期
	 * @return
	 */
	public String getLendDate() {
		if (lended) {
			Date date = new Date(lendDate);
			SimpleDateFormat sdf = new SimpleDateFormat("yyyy年MM月dd日");
			return sdf.format(date);
		} else {
			return "---";
		}
	}
	public void setName(String name) {
		this.name = name;
	}
	public void setPrice(double price) {
		this.price = price;
	}
	public void setCounter(int counter) {
		this.counter = counter;
	}
	
	/**
	 * 重写比較的方法
	 */
	@Override
	public int compareTo(Book other) {
		return (other.counter - this.counter);
	}

	@Override
	public String toString() {
		return " name=" + name + ", isbn=" + isbn
				+ ", price=" + price + ", lended=" + lended + ", counter="
				+ counter + ", lendDate=" + lendDate + "]";
	}
}

然后是 Manager

package com.lovo.BookManager;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

/**
 * @author Abe
 * @version 1.0
 * @created 05-十一月-2011 15:58:35
 */
public class BookManager {
	private List<Book> list = new ArrayList<Book>();

	public BookManager() {
		// 加入图书作为測试数据
		list.add(new Book("111", "编程思想", 1.5));
		list.add(new Book("222", "鹿鼎记", 0.5));
		list.add(new Book("333", "育儿百科", 1.2));
		list.add(new Book("444", "寻秦记", 0.7));
		list.add(new Book("555", "斗罗大陆", 1.1));
	}

	/**
	 * 方法：新增书籍
	 * @param Book
	 */
	public boolean add(Book book) {
		if (findByISBN(book.getIsbn()) == null) {
			list.add(book);
			return true;
		}
		return false;
	}

	/**
	 * 移除书籍
	 * @param isbn
	 */
	public boolean deleteByISBN(String isbn) {
		if (findByISBN(isbn) == null) {
			return false;
		} else {
			list.remove(findByISBN(isbn));
			return true;
		}
	}
	
	/**
	 * 方法：返回所有容器
	 * @return
	 */
	public List<Book> findAll() {
		return list;
	}

	/**
	 * 按isbn查找目标书籍
	 * @param isbn
	 */
	public Book findByISBN(String isbn) {
		for (Book b : list) {
			if (b.getIsbn().equals(isbn)) {
				return b;
			}
		}return null;
	}

	public Book[] findTop10() {
		if (list != null) {
			Book[] tempBook = new Book[list.size()];
			tempBook = list.toArray(tempBook);
			Arrays.sort(tempBook); //匿名内部类借口 A

			Book[] top10 = new Book[list.size() < 10 ? list.size() : 10];
			System.arraycopy(tempBook, 0, top10, 0, top10.length);
			return top10;
		} else {
			return null;
		}
	}

	/**
	 * 归还
	 * @param b
	 * @return 租金
	 */
	public double getBackFromUser(String isbn) {
		if (findByISBN(isbn) != null) {
			return findByISBN(isbn).returnBack();
		}
		return 0;
	}

	/**
	 * 借出
	 * @param b
	 * @return 是否借书成功
	 */
	public boolean lendedToUser(String isbn) {
		if (findByISBN(isbn) != null) {
			return findByISBN(isbn).lendOut();
		}
		return false;
	}
}

3.最后是控制台的功能验证

package com.lovo.BookManager;

import java.util.List;
import java.util.Scanner;

/**
 * @author Abe
 * @version 1.0
 * @created 05-十一月-2014 15:37:33
 */
public class SystemUI {
	
	public static void main(String[] args) {
		BookManager manager = new BookManager();
		Scanner sc1 = new Scanner(System.in);
		Scanner sc2 = new Scanner(System.in);
		
		do {
			int choice = 0;
			do {
				System.out.println("\n---------------\n");
				System.out.println("1. 新增图书");
				System.out.println("2. 删除图书");
				System.out.println("3. 改动图书");
				System.out.println("4. 查看全部图书");
				System.out.println("5. 查找图书");
				System.out.println("6. 借书");
				System.out.println("7. 还书");
				System.out.println("8. 查看排行榜");
				System.out.println("9. 退出系统");
				System.out.println("\n---------------\n");
				System.out.print("请选择: ");
				choice = sc2.nextInt();
			} while(choice < 1 || choice > 9);
			
			switch(choice) {
			case 1: 
				System.out.print("请输入书的编号: ");
				String isbn1 = sc1.nextLine();
				System.out.print("请输入书的名称: ");
				String name = sc1.nextLine();
				System.out.print("请输入书的日租金: ");
				double price = sc2.nextDouble();
				
				Book newBook = new Book(isbn1, name, price);
				System.out.println(manager.add(newBook)?
 "加入成功!" : "加入失败!");
				
				break;
			case 2: 
				System.out.print("请输入书的编号: ");
				String isbn2 = sc1.nextLine();
				
				System.out.println(manager.deleteByISBN(isbn2)? "删除成功!" : "删除失败!");
				
				break;
			case 3: 
				break;
			case 4: 
				List<Book> bookList = manager.findAll();
				System.out.println("名称\t\t日租金\t状态\t借出日期\t借出次数");
				for(Book b : bookList) {
					System.out.println(b.getName() + "\t\t" + b.getPrice() + "\t" + 
							(b.isLended()? "已借出" : "未借出") + "\t" +
							b.getLendDate() + "\t" + b.getCounter());
				}
				break;
			case 5: 
				System.out.print("请输入书的编号: ");
				String isbn3 = sc1.nextLine();
				
				Book temp = manager.findByISBN(isbn3);
				if(temp != null) {
					System.out.println("书名: " + temp.getName());
					System.out.println("日租金: " + temp.getPrice());
					System.out.println("借出状态: " + (temp.isLended()? "已借出" : "未借出"));
					System.out.println("借出日期: " + temp.getLendDate());
					System.out.println("借出次数: " + temp.getCounter());
				}
				else {
					System.out.println("没有此书!!!");
				}
				break;
			case 6: 
				System.out.print("请输入书的编号: ");
				String isbn4 = sc1.nextLine();
				
				System.out.println(manager.lendedToUser(isbn4)?
 "借出成功!" : "借出失败!");
				break;
			case 7: 
				System.out.print("请输入书的编号: ");
				String isbn5 = sc1.nextLine();
				
				System.out.println("请交纳租金: ￥" + manager.getBackFromUser(isbn5));
				break;
			case 8: 
				Book[] list = manager.findTop10();
				System.out.println("名称\t\t日租金\t状态\t借出日期\t借出次数");
				for(Book b : list) {
					System.out.println(b.getName() + "\t\t" + b.getPrice() + "\t" + 
							(b.isLended()? "已借出" : "未借出") + "\t" +
							b.getLendDate() + "\t" + b.getCounter());
				}
				break;
			case 9: 
				System.exit(0);
				break;
			}
		} while(true);
	}
}

除了改动，都能正常执行