public class User {
?? ?String id;
?? ?String name;
?? ?int rentNumber;
?? ?Book Rent[];
?? ?User(String id,String name){
?? ??? ?rentNumber=0;
?? ??? ?this.id = id;
?? ??? ?this.name = name;
?? ??? ?Rent = new Book[15];
?? ??? ?for(int i=0;i<15;i++){
?? ??? ??? ? Rent[i]=new Book("Z999"," ");
?? ??? ?}
?? ?}
?? ?void RentBook(Book b){
?? ??? ?Rent[rentNumber]=b;
?? ??? ?rentNumber++;
?? ?}
?? ?void Return(String bookId){
?? ??? ?int key=13;
?? ??? ?for(int i=0;i<15;i++){
?? ??? ??? ?if(bookId.equals(Rent[i].bookId)){
?? ??? ??? ??? ?key =i;
?? ??? ??? ?}
?? ??? ?}
?? ??? ?for(int i=key;i<14;i++){
?? ??? ??? ?Rent[key].setName(Rent[key+1].bookName);
?? ??? ??? ?Rent[key].setId(Rent[key+1].bookId);
?? ??? ?}
?? ??? ?rentNumber--;
?? ?}
?? ?
?? ?void RentList(){ ? ? ? //借閱信息
?? ??? ?if(rentNumber>0){
?? ??? ??? ?System.out.println("當(dāng)前借閱圖書：");
?? ??? ??? ?for(int i=0;i<rentNumber;i++){
?? ??? ??? ??? ?Rent[i].display();
?? ??? ??? ?}
?? ??? ?}
?? ??? ?
?? ??? ?else System.out.println("當(dāng)前無借閱圖書");
?? ?}
}

class Book{ ? //圖書類
?? ?String bookId;
?? ?String bookName;
?? ?Book(String Id,String Name){
?? ??? ?bookId = Id;
?? ??? ?bookName = Name;
?? ?}
?? ?void setId(String Id){
?? ??? ?bookId = Id;
?? ?}
?? ?void setName(String name){
?? ??? ?bookName = name;
?? ?}?? ?
?? ?void display(){
?? ??? ?System.out.println("Id:"+bookId+" ?"+"書名:"+bookName);
?? ?}
}

class Library{ ? ?//系統(tǒng)類
?? ?Book bookList[];
?? ?int bookNumber;
?? ?Library(){
?? ??? ?bookNumber=0;
?? ??? ? bookList = new Book[30];
?? ??? ?for(int i=0;i<30;i++){
?? ??? ??? ? bookList[i]=new Book("Z999"," ");
?? ??? ?}
?? ?}
?? ?void AddBook(Book b){ ?//增加
?? ??? ?bookList[bookNumber]=b;
?? ??? ?bookNumber++;
?? ?}
?? ?void FindBook(String Id){ ? ? ? ? ? ? ?//查詢
?? ??? ?for(int i=0;i<30;i++){
?? ??? ??? ?if(Id.equals(bookList[i].bookId)){
?? ??? ??? ??? ?bookList[i].display();
?? ??? ??? ?}
?? ??? ?}
?? ?}
?? ?void RewriteBook(String Id,String Name){//修改
?? ??? ?for(int i=0;i<30;i++){
?? ??? ??? ?if(Id.equals(bookList[i].bookId)){
?? ??? ??? ??? ?bookList[i].setName(Name);
?? ??? ??? ?}?? ??? ??? ?
?? ??? ?}
?? ?}
?? ?void DeleteBook(String Id){ ?//刪除
?? ??? ?int key=28;
?? ??? ?for(int i=0;i<30;i++){
?? ??? ??? ?if(Id.equals(bookList[i].bookId)){
?? ??? ??? ??? ?key =i;
?? ??? ??? ?}
?? ??? ?}
?? ??? ?for(int i=key;i<29;i++){
?? ??? ??? ?bookList[key].setName(bookList[key+1].bookName);
?? ??? ??? ?bookList[key].setId(bookList[key+1].bookId);
?? ??? ?}
?? ?}
}

public class Ex8{
?? ?public static void main(String args[]){
?? ??? ?Book book1= new Book("A001","Python數(shù)據(jù)分析實戰(zhàn)");
?? ??? ?Book book2 = new Book("A002","Python機器學(xué)習(xí)");
?? ??? ?Book book3 = new Book("A003","C++基礎(chǔ)教程");
?? ??? ?Library library = new Library();
?? ??? ?library.AddBook(book1); ? ? //增加圖書
?? ??? ?library.AddBook(book2);
?? ??? ?library.AddBook(book3);
?? ??? ?library.FindBook("A002"); ? ?//查詢圖書
?? ??? ?library.RewriteBook("A001", "碼農(nóng)翻身");//修改圖書
?? ??? ?book1.display();
?? ??? ?library.DeleteBook("A001");//刪除圖書
?? ??? ?User Bob = new User("20181532", "Bob");
?? ??? ?Bob.RentBook(book3); ? ?//借閱圖書
?? ??? ?Bob.RentList(); ? ? ? ? //個人借閱信息查詢。
?? ??? ?Bob.Return("A003"); ? ? //歸還圖書
?? ??? ?Bob.RentList(); ?
?? ??? ??? ??? ?
?? ?}
}