本篇文章給大家帶來了關于java的相關知識，其中主要介紹了關于怎么實現圖書管理系統的相關問題，包括了查找圖書、添加圖書、刪除圖書、借閱圖書等等內容，下面一起來看一下，希望對大家有幫助。

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一. 功能介紹

1.1 使用介紹

1.輸入姓名

2.選擇身份

3.根據身份打印不同功能菜單

1.2 基本框架

二、具體思路

book（包）

operation（功能包）

user（使用者包）

三、代碼實現

book（包）

Book（書類）

package book;/**  * User: gu'jiu  * Date: 2022-05-18  * Time: 14:45  * Description:書  */public class Book {     private String name;//書名     private String author;//作者     private double price;//價格     private String type;//類型     private boolean state;//書的狀態（已借出or未借出）      	//對書進行初始化，書的狀態不用進行初始化（默認未借出）     public Book(String name, String author, double price, String type) {         this.name = name;         this.author = author;         this.price = price;         this.type = type;         this.state = state;     }      public String getName() {         return name;     }      public void setName(String name) {         this.name = name;     }      public String getAuthor() {         return author;     }      public void setAuthor(String author) {         this.author = author;     }      public double getPrice() {         return price;     }      public void setPrice(double price) {         this.price = price;     }      public String getType() {         return type;     }      public void setType(String type) {         this.type = type;     }      public boolean isState() {         return state;     }      public void setState(boolean state) {         this.state = state;     }      @Override     public String toString() {         return "[" +                 "name='" + name + ''' +                 ", author='" + author + ''' +                 ", price=" + price +                 ", type='" + type + ''' +                 ", " + (state == true ? "已借出" : "未借出") +                 ']';     }}

BookList（書架類）

package book;/**  * User: gu'jiu  * Date: 2022-05-18  * Time: 14:52  * Description:書架  */public class BookList {     private Book[] books = new Book[10];     private int usedSize;      public BookList() {         books[0] = new Book("三國演義","羅貫中",19.9,"小說");         books[1] = new Book("西游記","吳承恩",29.9,"小說");         books[2] = new Book("紅樓夢","曹雪芹",26.9,"小說");         usedSize = 3;     }      public Book getBooks(int pos) {//輸入下標獲取該下標的這本書         return books[pos];     }      public void setBooks(int pos, Book book) {//輸入下標和一本書，在該下標放入一本書         this.books[pos] = book;     }      public int getUsedSize() {         return usedSize;     }      public void setUsedSize(int usedSize) {         this.usedSize = usedSize;     }}

operation（功能包）

IOperation（功能接口）

package operation;import book.BookList;/**  * User: gu'jiu  * Date: 2022-05-18  * Time: 15:07  * Description:接口  */public interface IOperation {     void work(BookList bookList);}

FindOperation（查找圖書）

package operation;import book.Book;import book.BookList;import java.util.Scanner;/**  * User: gu'jiu  * Date: 2022-05-18  * Time: 15:09  * Description:查找書籍信息  */public class FindOperation implements IOperation{     @Override     public void work(BookList bookList) {         System.out.println();         System.out.println("查找圖書");         System.out.println("------------------------");         Scanner scanner = new Scanner(System.in);         System.out.print("請輸入書的名稱:");         String name = scanner.nextLine();          //獲取書架中圖書數量         int size = bookList.getUsedSize();         //根據名字查找         for (int i = 0; i < size; i++) {             Book book = bookList.getBooks(i);             if (book.getName().equals(name)) {                 System.out.println(book);                 return;             }         }         System.out.println("未找到該書。");     }}

AddOperation（添加圖書）

package operation;import book.Book;import book.BookList;import java.util.Scanner;/**  * User: gu'jiu  * Date: 2022-05-18  * Time: 15:04  * Description:新增書籍  */public class AddOperation implements IOperation{     @Override     public void work(BookList bookList) {         System.out.println();         System.out.println("添加圖書");         System.out.println("------------------------");         Scanner scanner = new Scanner(System.in);         System.out.print("請輸入書名:");         String name = scanner.nextLine();         System.out.print("請輸入作者:");         String author = scanner.nextLine();         System.out.print("請輸入書的類型:");         String type = scanner.nextLine();         System.out.print("請輸入價格:");         double price = scanner.nextDouble();          Book book = new Book(name, author, price, type);         bookList.setBooks(bookList.getUsedSize(), book);//將書放入書架          bookList.setUsedSize(bookList.getUsedSize()+1);//書籍數量+1     }}

DelOperation（刪除圖書）

package operation;import book.Book;import book.BookList;import java.util.Scanner;/**  * User: gu'jiu  * Date: 2022-05-18  * Time: 15:05  * Description:刪除書籍  */public class DelOperation implements IOperation{     @Override     public void work(BookList bookList) {         System.out.println();         System.out.println("刪除圖書");         System.out.println("------------------------");         Scanner scanner = new Scanner(System.in);         System.out.print("請輸入要刪除的書名:");         String name = scanner.nextLine();          //獲取書架中現在有幾本書         int size = bookList.getUsedSize();         int i = 0;         //根據書名找到這個本書的下標         for (i = 0; i < size; i++) {             Book book = bookList.getBooks(i);             if (book.getName().equals(name)) {                 break;             }         }         if (i == size) {             System.out.println("刪除失敗，未找到該書。");             return;         }         //通過前移將書刪除         for (i = 0; i < size - 1; i++) {             bookList.setBooks(i,bookList.getBooks(i + 1));         }         bookList.setUsedSize(bookList.getUsedSize()-1);//書架中圖書數量-1         System.out.println("刪除成功。");     }}

BorrowOperation（借閱圖書）

package operation;import book.Book;import book.BookList;import java.util.Scanner;/**  * User: gu'jiu  * Date: 2022-05-18  * Time: 15:05  * Description:借閱書籍  */public class BorrowOperation implements IOperation{     @Override     public void work(BookList bookList) {         System.out.println();         System.out.println("借閱圖書");         System.out.println("------------------------");         Scanner scanner = new Scanner(System.in);         System.out.print("請輸入要借書的名稱:");         String name = scanner.nextLine();          //獲取書架中現在有幾本書         int size = bookList.getUsedSize();         for (int i = 0; i < size; i++) {             Book book = bookList.getBooks(i);             //判斷在書架中是否有這本書             if (book.getName().equals(name)) {                 //判斷書是否被借走                 if (!book.isState()) {                     System.out.println("借閱成功！");                     book.setState(true);//將書的狀態改為已借出                     return;                 } else {                     System.out.println("借閱失敗，該書已被別人借走。");                     return;                 }             }         }         System.out.println("借閱失敗，未找到該書。");     }}

ReturnOperation（歸還圖書）

package operation;import book.Book;import book.BookList;import java.util.Scanner;/**  * User: gu'jiu  * Date: 2022-05-18  * Time: 15:10  * Description:歸還書籍  */public class ReturnOperation implements IOperation{     @Override     public void work(BookList bookList) {         System.out.println();         System.out.println("歸還圖書");         System.out.println("------------------------");         Scanner scanner = new Scanner(System.in);         System.out.print("請輸入要還書的名稱:");         String name = scanner.nextLine();          //獲取書架中現在有幾本書         int size = bookList.getUsedSize();         for (int i = 0; i < size; i++) {             Book book = bookList.getBooks(i);             //判斷在書架中是否有這本書             if (book.getName().equals(name)) {                 //判斷書是否已被借走                 if (book.isState()) {                     System.out.println("歸還成功！");                     book.setState(false);//將書的狀態改為未借出                     return;                 } else {                     System.out.println("歸還失敗，該書已還未被借走。");                     return;                 }             }         }         System.out.println("歸還失敗，未找到該書。");     }}

DisplayOperation（打印圖書信息）

package operation;import book.Book;import book.BookList;/**  * User: gu'jiu  * Date: 2022-05-18  * Time: 15:06  * Description:打印全部書籍信息  */public class DisplayOperation implements IOperation{     @Override     public void work(BookList bookList) {         System.out.println();         System.out.println("顯示全部圖書");         System.out.println("------------------------");         int size = bookList.getUsedSize();         for (int i = 0; i < size; i++) {             Book book = bookList.getBooks(i);             System.out.println(book);         }     }}

ExitOperation（退出系統）

import book.BookList;/**  * User: gu'jiu  * Date: 2022-05-18  * Time: 15:08  * Description:退出系統  */public class ExitOperation implements IOperation{     @Override     public void work(BookList bookList) {         System.out.println();         System.out.println("退出系統。");         System.out.println("------------------------");         System.exit(0);     }}

user（使用者包）

User（使用者抽象類）

package user;import book.BookList;import operation.IOperation;/**  * User: gu'jiu  * Date: 2022-05-18  * Time: 15:11  * Description:使用者  */abstract public class User {     protected String userName;//使用者姓名     protected IOperation[] iOperations;//功能數組      public User(String userName) {         this.userName = userName;     }      public abstract int menu();          //輸入選擇，調用不同的功能     public void doOperation(int choice, BookList bookList) {         this.iOperations[choice].work(bookList);//動態綁定     }}

AdminUser（管理員）

package user;import operation.*;import java.util.Scanner;/**  * User: gu'jiu  * Date: 2022-05-18  * Time: 15:13  * Description:管理員  */public class AdminUser extends User{     public AdminUser(String userName) {         super(userName);         //管理員功能         this.iOperations = new IOperation[] {                 new ExitOperation(),                 new FindOperation(),                 new AddOperation(),                 new DelOperation(),                 new DisplayOperation()         };     }      @Override     public int menu() {         System.out.println();         System.out.println("hello " + this.userName + " 歡迎來到圖書館");         while(true) {             System.out.println("------------------------");             System.out.println("1.查找圖書");             System.out.println("2.新增圖書");             System.out.println("3.刪除圖書");             System.out.println("4.顯示全部圖書");             System.out.println("0.退出系統");             System.out.println("------------------------");             System.out.print("請輸入你的操作:");             Scanner scanner = new Scanner(System.in);             int choice = scanner.nextInt();             //保證輸入數字有效             if (choice > 4 || choice < 0) {                 System.out.println("輸入有誤請重新輸入。");             } else {                 return choice;             }         }     }}

NormalUser（普通用戶）

package user;import operation.*;import java.util.Scanner;/**  * User: gu'jiu  * Date: 2022-05-18  * Time: 15:13  * Description:學生  */public class NormalUser extends User{     public NormalUser (String userName) {         super(userName);         //用戶功能         this.iOperations = new IOperation[] {                 new ExitOperation(),                 new FindOperation(),                 new BorrowOperation(),                 new ReturnOperation(),         };     }      @Override     public int menu() {         System.out.println();         System.out.println("hello "+this.userName+" 歡迎來到圖書館");         while(true) {             System.out.println("------------------------");             System.out.println("1.查找圖書");             System.out.println("2.借閱圖書");             System.out.println("3.歸還圖書");             System.out.println("0.退出系統");             System.out.println("------------------------");             System.out.print("請輸入你的操作:");             Scanner scanner = new Scanner(System.in);             int choice = scanner.nextInt();             //保證輸入數字有效             if (choice > 3 || choice < 0) {                 System.out.println("輸入有誤請重新輸入。");             } else {                 return choice;             }         }     }}

Test類

import book.BookList;import user.AdminUser;import user.NormalUser;import user.User;import java.util.Scanner;/**  * User: gu'jiu  * Date: 2022-05-18  * Time: 15:20  * Description:圖書管理系統  */public class Test {     public static User login() {         System.out.println("歡迎使用圖書管理系統");         Scanner scanner = new Scanner(System.in);         System.out.print("請輸入您的姓名:");         String name = scanner.nextLine();          while(true){             System.out.println("-----------------------------");             System.out.println("請選擇您的身份:1>管理員 2>普通用戶");              System.out.print("請輸入：");             int choice = scanner.nextInt();              //保證輸入數字有效             if (choice == 1) {                 return new AdminUser(name);             } else if (choice == 2) {                 return new NormalUser(name);             } else {                 System.out.println("輸入有誤，請重新輸入。");             }         }     }     public static void main(String[] args) {         BookList bookList = new BookList();         User user = login();//向上轉型          while(true){             int choice = user.menu();             user.doOperation(choice, bookList);         }     }}

四、部分代碼（doOperation）解釋

主函數中的user.doOperation(choice, bookList);中的doOperation方法比較難理解，我們來解釋一下

1.user.引用的可能是兩個對象

2.在實例化這對象的時候，在構造方法中，我們已經將iOperations[]準備好了。

3.根據輸入下標（例如：2）訪問相應對象，再調用work方法。

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