思路：创建三各类 books 相当于书类 记录着书的属性和获取书的方法 mannagerbooks 管理图书 里面创建的一个books类型的数组 相当于书架 里面实现增删改查的方法 TestBooks 测试类记录着调各个类的方法实现菜单。
package com.hainiu.book;
import java.util.Scanner;
//书的属性类
class Books{
private String name;
private double price;
private int number;
public Books(){
}
public Books(String name, double price, int number) {
this.name = name;
this.price = price;
this.number = number;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public double getPrice() {
return price;
}
public void setPrice(double price) {
this.price = price;
}
public int getNumber() {
return number;
}
public void setNumber(int number) {
this.number = number;
}
public String show(){
return name +","+ price + "," + number;
}
}
class ManagerBooks{
//创建一个数组 相当于书架存放book
private Books [] books = new Books[100];
//添加
public void add(Books book){
//循环查看书架 如果没有这本书 那么增加 如果有那么提示已经有这本书了
for (int i = 0; i < books.length; i++) {
if(books[i]==null){
books[i]=book;
System.out.println("添加成功");
break;
}else{
System.out.println("该书已存在");
}
}
}
//修改
public void update(int number,double price){
//循环查看书架 如果有这本书 那么修改 如果没有提示没有这本书
for (int i = 0; i < books.length; i++) {
if(books[i].getNumber()==number){
//如果有这个编号 那么改他的价格
books[i].setPrice(price);
System.out.println("修改成功");
}else{
System.out.println("该书不存在");
}
break;
}
}
//删除
public void delete(int number){
for (int i = 0; i < books.length; i++) {
if(books[i].getNumber()==number){
//数组删除用后一个覆盖前一个
for (int j = i; j < books.length-1; j++) {
books[j]=books[j+1];
}
if(books[books.length-1]!=null){
books[books.length-1]=null;
}
System.out.println("删除成功");
break;
}
}
}
//查询
public void query(){
System.out.println("图书编号\t图书名称 \t图书价格");
for (Books b : books) {
if(b == null){
break;
}
System.out.println(b.show());
}
}
//退出
}
public class TestBooks {
public void startsystem(){
Scanner sc = new Scanner(System.in);
ManagerBooks mgb = new ManagerBooks();
System.out.println("-----欢迎来到菜单-----");
System.out.println("1、添加 2、修改 3、删除 4、查询 5、退出");
int number;
String name;
double price;
while(true){
System.out.println("请选择菜单");
//录入数字的
int n =sc.nextInt();
switch(n){
//如果是1 那么就是添加 name +","+ price + "," + number;
case 1:
System.out.println("欢迎来到添加页面");
System.out.println("请输入编号");
number = sc.nextInt();
System.out.println("请输入书名");
name = sc.next();
System.out.println("请输入价格");
price = sc.nextDouble();
Books books = new Books( name, price, number);
mgb.add(books);
break;
//如果是2那么就是修改页面
case 2:
System.out.println("欢迎来到修改页面");
System.out.println("输入要修改的编号");
number = sc.nextInt();
System.out.println("输入改的价格");
price = sc.nextDouble();
mgb.update(number, price);
break;
case 3:
System.out.println("欢迎来到删除页面");
System.out.println("输入要删除的编号");
number = sc.nextInt();
mgb.delete(number);
break;
case 4:
System.out.println("欢迎来到查询页面");
mgb.query();
break;
case 5:
System.out.println("退出页面");
System.exit(0);
}
}
}
public static void main(String[] args) {
// TODO Auto-generated method stub
new TestBooks().startsystem();
}
}