借书系统代码 求大神指点

import java.util.*;

public class booktest{

/**

* @param args

*/

public static void main(String[] args) {

// TODO Auto-generated method stub

String[] bname={"高等数学","计算机","口语","Java","c++"};

System.out.println("请输入书名或图书序号！");

System.out.println("请选择 1书名   0 序号");

Scanner s=new Scanner(System.in);

w:for(;;){

int a=s.nextInt();

if(a==1)

{

System.out.println("请输入书名：");

String a1=s.next();

for(String b:bname)

{if(b.equals(a1))

{System.out.println("存在");

continue w;}}

//else

System.out.println("不存在");

}else if(a==0)

{

System.out.println("请输入序号：");

try {

int a2=s.nextInt();

if(a2>=0 && a2<bname.length){

for(String b:bname)

{System.out.println(bname[a2-1]);

continue w;

}}

else 

System.out.println("图书不存在！");

} catch (Exception e) {

// TODO: handle exception

e.printStackTrace();

System.out.println("输入错误，请重新输入！");

}

finally

{System.out.println("欢迎您下次光临");}

}

}

}

}