package BBB;
import java.util.Scanner;

public class BookSystem {
int choice;
public int getChoice() {
return choice;
}

public void setChoice(int choice) {
    this.choice = choice;
}

public String[] book={"沉默的大多数","红拂夜奔","黄金时代","绿毛水怪","三十而立","猫","万寿寺"}; 
public String[] number={"1","2","3","4","5","6","7"};

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

do
    try{
        Scanner input1=new Scanner(System.in);
        choice=input1.nextInt();
}catch(Exception e){
    System.out.println("请输入1或2！");
}while(choice!=1&&choice!=2);

}
public void method1()throws NoExistException{
    boolean bool=true;
    do
    try{System.out.println("请输入图书序号");
    Scanner input2=new Scanner(System.in);
    double num=input2.nextDouble();
    if(num<number.length)
    {System.out.println("你要找的书序号是："+number[(int) num-1]+",书名是："+book[(int) num-1]);
    bool=false;
    }
    if(num>number.length)
    {   bool=true;}
    if(bool==true)
        {throw new NoExistException();}
    }catch(NoExistException e){
        e.show();
    }while(bool==true);
}

public void method2()throws NoExistException{
    System.out.println("请输入图书书名：");
     boolean bool = true;
do
   try{
        Scanner input2=new Scanner(System.in);
       String name=input2.next();
        for(int i=0;i<book.length;i++) {
        if(book[i].equals(name)){
            System.out.println("你要找的书序号是："+number[i]+",书名是："+book[i]);
         bool = false;
         }}
        if(bool==true)
             throw new NoExistException();
    }catch(NoExistException e){
        e.show();
    }while(bool==true);

}

}
package BBB;

@SuppressWarnings("serial")
public class NoExistException extends Exception {
public void show(){
System.out.println("该书不存在，请重新输入！");
}
}

public class Test {

/**
 * @param args
 * @throws NoExistException 
 */
public static void main(String[] args) throws NoExistException {
    // TODO Auto-generated method stub
    BookSystem user=new BookSystem();
    user.hello();
    switch(user.choice){
    case 1:
            user.method1();
    break;
    case 2:
            user.method2();
    break;}
    System.out.println();
    System.out.println();
    System.out.println("谢谢使用。");
}