代碼?:

package?borrowBook;
?import?java.util.Scanner;
?
?public?class?BorrowBook??{
?????private?Book?[]books?=?{new?Book("數據結構",1),
?????????????????????????????new?Book("高數",2)};
?????private?static?Boolean?=?false;
?????private?static?boolean?=?false;
?????public?void?cam_1()?throws?InputException{
?????????Scanner?scanner?=?new?Scanner(System.);
?????????System..println("輸入圖書名稱：");
?????????String?bookname?=?scanner.next();
?????????for(Book?i:books){
?????????????if(bookname.equals(i.getName())){
?????????????????i.getBook();
?????????????????=?true;
?????????????????break;
?????????????}
?????????}
?????????if(!){
?????????????throw?new?InputException("圖書不存在！");
?????????}
?????}
?
?????public?void?cam_2()?throws?InputException{
?????????Scanner?scanner?=?new?Scanner(System.);
?????????try{
?????????????System..println("輸入圖書序號：");
?????????????int?bookNumber;
?????????????if(scanner.hasNextInt()){
?????????????????bookNumber=scanner.nextInt();
?????????????}else{
?????????????????scanner.next();
?????????????????=?true;
?????????????????throw?new?InputException("命令輸入錯誤！請根據提示輸入數字命令！");
?????????????}
?????????????for(Book?i:books){
?????????????????if(bookNumber==i.getBookNumber()){
?????????????????????i.getBook();
?????????????????????=?true;
?????????????????????break;
?????????????????}
?????????????}
?????????????if(!)?{
?????????????????throw?new?InputException("圖書不存在！");
?????????????}
?????????}catch(InputException?e){
?????????????e.printMessage();
?????????????if(){
?????????????????=?false;
?????????????????new?BorrowBook().cam_2();
?????????????}else{
?????????????????new?BorrowBook().(new?String[1]);
?????????????}
?????????}
?????}
?
?public?static?void?main(String[]?args)?throws?InputException?{
?
?????????Scanner?scanner?=?new?Scanner(System.);
?????????while(true){
?????????????try{
?????????????????System..println("輸入命令：1-按照名稱查找圖書；2-按照序號查找圖書");
?????????????????String?cammand?=?scanner.next();
?????????????????if(cammand.equals("1")){new?BorrowBook().cam_1();
?????????????????}else?if(cammand.equals("2")){new?BorrowBook().cam_2();
?????????????????}else{
?????????????????????throw?new?InputException("命令輸入錯誤！請根據提示輸入數字命令！");
?????????????????}
?????????????????break;
?????????????}catch(InputException?e){
?????????????????e.printMessage();
?????????????}
?????????????}
?????????}
?????}
?class?Book{
?????private?String?bookName;private?int?bookNumber;public?Book?(String?name,int?number){
?????????bookName?=?name;
?????????bookNumber?=?number;
?????};
?????public?String?getName(){return?bookName;
?????}
?????public?int?getBookNumber(){return?bookNumber;
?????}
?????public?void?getBook(){System..println("book:"+bookName);
?????}
?}
?
?
?class?InputException?extends?Exception?{
?????private?String?message;
?????public?InputException(){}
?????public?InputException(String?message){
?????????super(message);
?????????this.message?=?message;
?????}
?????public?void?printMessage(){
?????????System..println(message);
?????}
?}

截圖 :