java第三季—图书馆查询系统

package com.imooc;

import java.util.Scanner;

public class Book {

/**
 * @param args
 */
public static void main(String[] args) {
    // TODO Auto-generated method stub
    Book bk=new Book();
    String[] bookName={"语文","数学","英语","物理","化学","生物"};
    System.out.println("欢迎使用图书管理系统");           
    while(true){
    System.out.println("请选择图书查询方式(0.退出)：");
    System.out.println("1.通过书名查询\t2.通过序号查询");                       
        Scanner input=new Scanner(System.in);               
        try {   
        String name;
        int sel=input.nextInt();
        if(0==sel)
        {   System.out.println("谢谢使用，再见！");
            return;
        }
        switch(sel){
        case 1:
            System.out.println("请输入书名：");
            name=bk.bookname(bookName);
            System.out.println("已找到book："+name);
            break;
        case 2:
            System.out.println("请输入序号：");
            name=bk.booknum(bookName);
            System.out.println("已找到book："+name);
            break;
        default:System.out.println("输入错误！");
        }

    } catch (Exception e) {
        // TODO: handle exception
        System.out.println("图书不存在！");   
    }
        }
}
public String bookname(String[] book) throws Exception{

    Scanner input=new Scanner(System.in);
    String name=input.next();
    for(int i=0;i<book.length;i++){
        if(name.equals(book[i])){
            return book[i];
        }
    }       
    throw new Exception("图书不存在！");

}
public String booknum(String[] book) throws Exception{
    Scanner input=new Scanner(System.in);
    int id=input.nextInt();
    if(id>0 && id<=book.length){
        return book[id-1];
    }
        throw new Exception("图书不存在！");

}

}