作业提交 。

InputException.java

package com.imooc.test;

public class InputException extends Exception {

     public InputException() {

         super();

         System.out.println("命令输入错误！请根据提示输入数字命令！");

     }

     public InputException(String message) {

         super(message);

         System.out.println(message);

     }

}

BookBorrow.java

package com.imooc.test;

import java.util.Arrays;

import java.util.InputMismatchException;

import java.util.Scanner;

public class BookBorrow {

     private static String[] books = { "高数", "积分变换", "线性代数", "马克思哲学" };

     public static void main(String[] args) {

         // TODO Auto-generated method stub

         BookBorrow bkb = new BookBorrow();

         bkb.borrow();

     }

     public void borrowByName(Scanner input) throws InputException {

         System.out.println("输入图书名称：");

         String name = input.next();

         if (-1 == Arrays.binarySearch(books, name)) {

              System.out.println("图书不存在！");

             throw new InputException();

         } else {

             System.out.println("book: " + name);

         }

     }

     public void borrowByNumber(Scanner input) throws InputException {

         System.out.println("输入图书序号：");

         int num = input.nextInt();

         if (num < 1 || num > books.length) {

              System.out.println("图书不存在！");

              throw new InputException();

         } else {

              System.out.println("book: " + books[num - 1]);

         }

     }

     public void borrow() {

         Scanner input = new Scanner(System.in);

         System.out.println("输入命令：1-按照名称查找图书；2-按照序号查找图书");

         try {

             switch (input.nextInt()) {

                 case 1:

                      borrowByName(input);

                      break;

                 case 2:

                     borrowByNumber(input);

                     break;

                 default:

                      System.out.println("命令输入错误！请根据提示输入数字命令！");

                     borrow();

                     break;

             }

         } catch(InputException e) {

         }catch (InputMismatchException e) {

             System.out.println("命令输入错误！请根据提示输入数字命令！");

         } catch (Exception e) {

             // TODO: handle exception

             e.printStackTrace();

         } finally {

             borrow();

             input.close();

         }

     }

}