交作业了啊啊啊啊
import java.util.Arrays;
import java.util.Scanner;
public class BorrowBook {
public static void main(String[] args) {
// TODO Auto-generated method stub
BorrowBook book = new BorrowBook();
book.Select();
}
public void Select() {
String[] books = new String[] {"java基础","水浒传","红楼梦","西游记","数据结构"};
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\"");
Scanner input = new Scanner(System.in);
int num = input.nextInt();
try {
if(num == 1) {
System.out.println("请输入图书名称：");
Scanner input1 = new Scanner(System.in);
String name = input1.nextLine();
boolean ture = Arrays.asList(books).contains(name);
if(ture) {
System.out.println("您输入的"+ name +"存在");
}else {
throw new NoBookExecption();
}
}else if(num == 2) {
System.out.println("请输入图书序列号：");
Scanner input2 = new Scanner(System.in);
int xuhao = input2.nextInt();
if(xuhao>=0 && xuhao<books.length) {
System.out.println("您要查询的图书名称为"+books[xuhao-1]);
}else {
throw new CommandExecption();
}
}
}catch(CommandExecption e){
System.out.println("你输入的命令有误！请检查后重新输入：");
Select();
}catch(NoBookExecption e) {
System.out.println("图书不存在！请重新输入你要查询的名称：");
Select();
}
}
}自定义异常类 CommandExecption类（命令输入有误）
public class CommandExecption extends Exception{
public CommandExecption() {//无参方法
}
public CommandExecption(String message) {//有参方法
super(message);
}
}自定义异常类
//图书不存在异常
public class NoBookExecption extends Exception{
public NoBookExecption() {//无参方法
}
public NoBookExecption(String message) {//有参方法
super(message);
}
}
