JAVASE之图书管理系统

import java.util.Scanner;
/**
 * 图书管理系统2.0
 * @author com
 *
 */
public class BookManage {
	
	private static Scanner sc = new Scanner(System.in);
	private static int n = 0;
	private int number;
	private String name;
	private double price;
	static {
		System.out.println("- 图书管理系统2.0版 -");
		System.out.println("  1.添加");
		System.out.println("  2.修改");
		System.out.println("  3.删除");
		System.out.println("  4.查询");
		System.out.println("  5.退出");
	}
	public BookManage(){
		
	}
	public BookManage(int number,String name,double price) {
		this.number = number;
		this.name = name;
		this.price = price;
	}
	public static void main(String[] args) {
		BookManage book = new BookManage();
		BookManage[] BM = new BookManage[200];
		book.menu(book,BM);
	}
	/*
	 * 菜单选择
	 */
	public void menu(BookManage book,BookManage[] BM) {
		
		System.out.print("* 请输入菜单选择：");
		int input = sc.nextInt();
		if(input == 1) {
			book.add(BM,n);
			book.menu(book,BM);
		}if(input == 2) {
			book.update(BM);
			book.menu(book,BM);
		}if(input == 3) {
			book.delete(BM);
			book.menu(book,BM);
		}if(input == 4) {
			book.query(BM);
			book.menu(book,BM);
		}if(input == 5) {
			book.exit();
			book.menu(book,BM);
		}
	}
	/**
	 * 添加方法
	 */
	public void add(BookManage[] BM,int n) {
//		System.out.println("--------------add()---------------");
		System.out.print("--请输入编号：");
		int number = sc.nextInt();
		System.out.print("--请输入图书名：");
		String name = sc.next();
		System.out.print("--请输入价格：");
		double price = sc.nextDouble();
		//把输入的属性通过构造函数传入类数组对象中
		BM[n] = new BookManage(number,name,price);
		System.out.println("添加成功！");
		BookManage.n++;
//		System.out.println("BookManage.n = "+BookManage.n);
	}
	/**
	 修改方法
	 */
	public void update(BookManage[] BM) {
//		System.out.println("--------------update()---------------");
		System.out.print("--输入要修改的编号：");
		int n = sc.nextInt();
		if(BM[n-1] != null) {
			System.out.print("--输入新的图书价格：");
			double m = sc.nextDouble();
			System.out.println("================");
			for(int i=0;i<=n-1;i++) {
				if(BM[i].getNumber() == n) {
					BM[i].setPrice(m);
				}
			}
			System.out.println("修改成功");
		}else{
			System.out.println("--------不存在此编号！----------");
		}
	}
	/**
	 删除方法
	 */
	public void delete(BookManage[] BM) {
//		System.out.println("--------------delete()---------------");
		System.out.println("输入要删除的图书编号：");
		int n = sc.nextInt();
		if(BM[n-1] != null) {
			for(int i=0;i<=n-1;i++) {
				if(BM[i].getNumber() == n) {
					BM[i] = null;
				}
			}
			System.out.println("删除成功！");
		}else {
			System.out.println("----不存在此编号！-----");
		}
	}
	/**
	 查询方法
	 */
	public void query(BookManage[] BM) {
//		System.out.println("--------------query()---------------");
		System.out.println("图书编号"+"        图书名称"+"  图书价格");
		for(int i=0;i<=n-1;i++) {
			if(BM[i] != null) {
				System.out.println(BM[i].getNumber()+"      "+BM[i].getName()+"  "+BM[i].getPrice());
			}
		}
	}
	/**
	 退出方法
	 */
	public void exit() {
//		System.out.println("--------------exit()---------------");
		System.exit(0);
	}
	
	public int getNumber() {
		return this.number;
	}
	public void setNumber(int number) {
		this.number = number;
	}
	public String getName() {
		return this.name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public double getPrice() {
		return this.price;
	}
	public void setPrice(double price) {
		this.price = price;
	}
	
}