目录
一、菜单
该图书管理系统的菜单界面主要有以下两种：
二、基本框架
1.book包
因为是图书管理系统，所以可以先从书（book）这个包开始。
book包中有book类和bookList类
1.1 book类
在book类中存放中图书的各种属性，书名、作者、价格、种类、借出状态。
private String name;
private String autor;
private int price;
private String type;
private boolean isBorrowed;再生成对应的构造方法：（Alt + insert） + Construct+（Crtl+鼠标）
鼠标右键 + Generate + Construct+（Crtl+鼠标）
生成以下代码：
public Book(String name, String autor, int price, String type) {
this.name = name;
this.autor = autor;
this.price = price;
this.type = type;
}再生成对应属性的get和set方法：（Alt + insert）+ Getter and Setter +（Crtl+鼠标)
生成以下代码：
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAutor() {
return autor;
}
public void setAutor(String autor) {
this.autor = autor;
}
public int getPrice() {
return price;
}
public void setPrice(int price) {
this.price = price;
}
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
public boolean isBorrowed() {
return isBorrowed;
}
public void setBorrowed(boolean borrowed) {
isBorrowed = borrowed;
}最后再重写toString方法：（Alt + insert）+ toString() +（Crtl+鼠标）
其中isBorrowed可以改写为下面三位运算符的形似：
1.2 bookList类
bookList类更像是一个书架，书是放在里面的。先创建Book数组，同时可以用useSized来记录图书数量。同时也可以放三本书在书架里面，方便后面运行功能。
private Book[] books = new Book[10];
private int useSized = 0;
public BookList(){
this.books[0] = new Book("三国演义","罗贯中",15,"小说");
this.books[1] = new Book("西游记","吴承恩",14,"小说");
this.books[2] = new Book("红楼梦","曹雪芹",15,"小说");
this.useSized = 3;
}再生成useSized的get和set方法：（Alt + insert） + Getter and Setter +（Crtl+鼠标)
public int getUseSized() {
return useSized;
}
public void setUseSized(int useSized) {
this.useSized = useSized;
}2.use包
写完部分book包的内容，我们可以开始写use包、用户方面的内容。从一开始的菜单可以得知，用户分为管理员和普通用户。而这两者之间有一些相同的属性：都有菜单，都有用户姓名。所以可以写一个User来被它们继承。
ues包中有User类、AdminUser类和NormalUser类
2.1 User类
为了保证name权限合理性，对应的访问修饰限定符为protected
同时生成对应的构造方法：（Alt + insert） + Construct+ 鼠标
public class User {
protected String name;
public User(String name) {
this.name = name;
}
}2.2 AdminUser类
AdminUser类继承（extends）User类，所以要在AdminUser中构造方法要重写User中的构造方法
对应构造方法的生成：（Alt + insert）+ Overr Methodes + 鼠标
public class AdminUser extends User{
public AdminUser(String name) {
super(name);
}
} 2.3 NormalUser类
同AdminUser类，步骤同上
public class NormalUser extends User{
public NormalUser(String name) {
super(name);
}
} 2.4 用户菜单
考虑到 AdminUser类和NormalUser类都有各自对应的菜单，所以可以把User类写成抽象类。同时里面写抽线方法menu。
public abstract class User {
protected String name;
public IOperation[] iOperations;
public User(String name) {
this.name = name;
}
public abstract int meun();
}因为User类变为抽象类，其中有抽象方法menu，AdminUser类和NormalUser类要对meun进行重写，同时添加各自的界面
AdminUser类
public class AdminUser extends User{
public AdminUser(String name) {
super(name);
}
@Override
public int meun() {
System.out.println("**********");
System.out.println("1.查找图书");
System.out.println("2.新增图书");
System.out.println("3.删除图书");
System.out.println("4.显示图书");
System.out.println("0.退出系统");
System.out.println("**********");
System.out.println("请输入需要的操作：");
}
}NormalUser类
public class NormalUser extends User{
public NormalUser(String name) {
super(name);
}
@Override
public int meun() {
System.out.println("**********");
System.out.println("1.查找图书");
System.out.println("2.借阅图书");
System.out.println("3.归还图书");
System.out.println("0.退出系统");
System.out.println("**********");
System.out.println("请输入需要的操作：");
}
3.opera包
在写完book包和use包的部分内容后，我们可以开始来写不同用户所对应的功能
opera包中有AddIOperation类、BorrowedIOperation类、DelIOperation类、ExitIOperation类、
FindIOperation类、IOperation接口、ReturnIOperation类、ShowIOperation类。
3.1 IOperation接口
在创建class文件时，选择Interface，创建接口
并在其中创建work方法
public interface IOperation {
void work(BookList bookList);
}
3.2 AddIOperation类
AddIOperation类去使用IOperation接口（implements）。
其中需要重写work方法：（Alt + insert）+ Overr Methodes + 鼠标
然后对其中的内容进行重写：
public class AddIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("新增图书...");
}
}3.3 剩余类如下
步骤同上：接口 + 重写方法。
BorrowedIOperation类
public class BorrowedeIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("借阅图书...");
}
}DelIOperation类
public class DelIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("删除图书...");
}ExitIOperation类
public class ExitIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("退出系统...");
}FindIOperation类
public class FindIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("查阅图书...");
}ReturnIOperation类
public class ReturnIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("归还图书...");
}ShowIOperation类
public class ReturnIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("归还图书...");
}4.Main类
上面的框架搭建的差不多了，现在可以写Main主函数来进行运行。
4.1 login方法
既然要运行该框架，那就需要一个方法来进行，这里创建出login方法来进行
开始界面的思路时：输入姓名，输入是什么类型的用户，并返回对应的菜单
public static User login(){
System.out.println("请输入你的姓名：");
Scanner sc = new Scanner(System.in);
String name = sc.nextLine();
System.out.println("请输入你的身份：1.管理员 2.普通成员");
int choice = sc.nextInt();
if(choice == 1){
return new AdminUser(name);
}else{
return new NormalUser(name);
}
}4.2 main函数
接下来通过login方法进行登录
public class Main {
public static User login(){
System.out.println("请输入你的姓名：");
Scanner sc = new Scanner(System.in);
String name = sc.nextLine();
System.out.println("请输入你的身份：1.管理员 2.普通成员");
int choice = sc.nextInt();
if(choice == 1){
return new AdminUser(name);
}else{
return new NormalUser(name);
}
}
public static void main(String[] args) {
BookList bookList = new BookList();
User user = login();
while(true){
int choice = user.meun();
}
}
}此时通过调试可以发现，最后输出的需求并不能直接实现
要想，输入 1，返回查找图书，我们还需要两个步骤：
- 完善管理员菜单和普通用户菜单
- 在User类里添加 doIOperation方法。
对于完善各自对应的菜单，我们能想到：如何使输入数字能进行对应的功能。
对应的功能可以放在一个数组里，然后通过数组下标进行输出。所以在User类添加
User类
public IOperation[] iOperations;在AdminUser类和NormalUser中也要有对应的改动
1.搭建ioperation数组
2.使菜单能返回输入的值
AdminUser类
public class AdminUser extends User{
public AdminUser(String name) {
super(name);
//1.搭建ioperation数组
this.iOperations = new IOperation[]{
new ExitIOperation(),
new FindIOperation(),
new AddIOperation(),
new DelIOperation(),
new ShowIOperation()
};
}
@Override
public int meun() {
System.out.println("**********");
System.out.println("1.查找图书");
System.out.println("2.新增图书");
System.out.println("3.删除图书");
System.out.println("4.显示图书");
System.out.println("0.退出系统");
System.out.println("**********");
//2.使菜单能返回输入的值
System.out.println("请输入需要的操作：");
Scanner sc = new Scanner(System.in);
int choice = sc.nextInt();
return choice;
}
}public class NormalUser extends User{
public NormalUser(String name) {
super(name);
this.iOperations = new IOperation[]{
new ExitIOperation(),
new FindIOperation(),
new BorrowedIOperation(),
new ReturnIOperation()
};
}
@Override
public int meun() {
System.out.println("**********");
System.out.println("1.查找图书");
System.out.println("2.借阅图书");
System.out.println("3.归还图书");
System.out.println("0.退出系统");
System.out.println("**********");
System.out.println("请输入需要的操作：");
Scanner sc = new Scanner(System.in);
int choice = sc.nextInt();
return choice;
}
}完成上面步骤，我们可以获取输入值，接下来就可以写doIOperation方法来让打通这条路
因为这是用户所使用的，所以把它写在User类中
User类最终的User如下图所示：
public abstract class User {
protected String name;
public IOperation[] iOperations;
public User(String name) {
this.name = name;
}
public abstract int meun();
public void doIOperation(int choice, BookList bookList){
iOperations[choice].work(bookList);
}
}main方法为
public static void main(String[] args) {
BookList bookList = new BookList();
User user = login();
while(true){
int choice = user.meun();
user.doIOperation(choice,bookList);
}
}运行结果为：
三、具体运行
3.1 ExitIOperation类
退出系统
在后面加 System.exit(0)。在程序运行后输入0便能退出循环，结束运行。
public class ExitIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("退出系统...");
System.exit(0);
}
}3.2 ShowIOperation类
显示图书
书是在书架上的，这就是说我们只要循环遍历书架便可以了。
其中可能存在的问题是不知道书架上有几本书，不过在一开始就创建了UsedSized来确定书本数。
为了能输出书，我们需要实例化书架上的书，但书架被private修饰，这时在BookList类里添加就需要get和set方法
BookList类
public void setBooks(Book[] books) {
this.books = books;
}
public Book[] getBooks(){
return books;
}
这是IDEA生成的get和set方法，仔细看其中和我们的需求并不一样，我们需要每一本书，而不是这个书架本身，所以可以改为下面的内容
public Book getBook(int pos) {
return books[pos];
}
public void setBook(int pos,Book book) {
this.books[pos] = book;
}最后，应用for循环来遍历书架上的每一本书
public class ShowIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("显示图书...");
int currentSize =bookList.getUseSized();
for (int i = 0; i < currentSize; i++) {
Book book = bookList.getBook(i);
System.out.println(book);
}
}
}3.3 AddIOperation类
新增图书
新增图书可以分为四步：
- 判断书架是否放满
- 输入这本书的信息
- 判断书架里有没有这本书
- 插入这本书
其中主要是1.判断书架是否放满上面，我们需要在BookList类中添加getBooks方法，来获取数组的长度。
BookList类
public Book[] getBooks(){
return books;
}AddIOperation类
public class AddIOperation implements IOperation{
@Override
public void work(BookList bookList) {
//1.判满
int currentSize = bookList.getUseSized();
if(currentSize == bookList.getBooks().length){
System.out.println("书放满了");
}
//2.插入图书信息
System.out.println("新增图书...");
System.out.println("请输入书名：");
Scanner sc = new Scanner(System.in);
String name = sc.nextLine();
System.out.println("请输入作者：");
String autor = sc.nextLine();
System.out.println("请输入价格：");
Scanner sc1 = new Scanner(System.in);
int price = sc1.nextInt();
System.out.println("请输入类型：");
String type = sc.nextLine();
Book newbook = new Book(name,autor,price,type);
//3.判断书架有没有这本书
for (int i = 0; i < currentSize; i++) {
Book book = bookList.getBook(i);
if(book.getName().equals(name)){
System.out.println("书架里有这本书,不能插入");
return;
}
}
//4.插入这本书
bookList.setBook(currentSize,newbook);
bookList.setUseSized(currentSize + 1);
System.out.println("新增图书成功");
}
}3.4 BorrowedIOperation类
借阅图书
通过书名来借阅图书，通过遍历数组中的书来确定
- 是否有这本书
- 是否被借阅
public class BorrowedIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("借阅图书...");
System.out.println("请输入要借阅的图书：");
Scanner sc = new Scanner(System.in);
String name = sc.nextLine();
int currentSize = bookList.getUseSized();
for (int i = 0; i < currentSize; i++) {
Book book = bookList.getBook(i);
if(book.getName().equals(name)){
if(book.isBorrowed() == true){
System.out.println("该图书已被借阅");
return;
}
book.setBorrowed(true);
System.out.println("借阅成功");
return;
}
}
System.out.println("没有你要借阅的图书");
}
}3.5 ReturnIoperation类
归还图书
归还图书的整体逻辑和借阅图书的类似，通过代码也能看出这一点
ublic class ReturnIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("归还图书...");
System.out.println("请输入你要归还的图书：");
Scanner sc = new Scanner(System.in);
String name = sc.nextLine();
int currentSize = bookList.getUseSized();
for (int i = 0; i < currentSize; i++) {
Book book = bookList.getBook(i);
if(book.getName().equals(name)){
if(book.isBorrowed() == false){
System.out.println("该图书未被借阅，不能归还");
return;
}
book.setBorrowed(false);
System.out.println("归还成功");
}
}
}
}3.6 DelIoperation类
删除图书
删除图书的思路大致如下
- 遍历书架来找到这本书
- 找到即开始删除这本书
public class DelIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("删除图书...");
System.out.print("请输入要删除的图书：");
Scanner sc = new Scanner(System.in);
String name = sc.nextLine();
int currentSize = bookList.getUseSized();
int pos = -1;//pos用来记录找到图书的下标
//1.找到这本书
int i = 0;
for (; i < currentSize; i++) {
Book book = bookList.getBook(i);
if(book.getName().equals(name)){
pos = i;
break;
}
}
if(i == currentSize){
System.out.println("没有你要删除的图书");
return;
}
//2.开始删除图书
for (int j = pos; j < currentSize - 1; j++) {
//j < currentSize - 1,如果只是currentSize,会越界
//bookList[j] = bookList[j+1];
Book book = bookList.getBook(j+1);//创建一个book对象，里面放book【j+1】
bookList.setBook(j,book);
}
bookList.setUseSized(currentSize -1);
System.out.println("删除成功");
}
}总代码
book包
Book类
package book;
/**
* Created with IntelliJ IDEA.
* Description:
* User:
* Date: 2024-07-14
* Time: 14:07
*/
public class Book {
private String name;
private String autor;
private int price;
private String type;
private boolean isBorrowed;
public Book(String name, String autor, int price, String type) {
this.name = name;
this.autor = autor;
this.price = price;
this.type = type;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAutor() {
return autor;
}
public void setAutor(String autor) {
this.autor = autor;
}
public int getPrice() {
return price;
}
public void setPrice(int price) {
this.price = price;
}
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
public boolean isBorrowed() {
return isBorrowed;
}
public void setBorrowed(boolean borrowed) {
isBorrowed = borrowed;
}
@Override
public String toString() {
return "Book{" +
"name='" + name + '\'' +
", autor='" + autor + '\'' +
", price=" + price +
", type='" + type + '\'' +
", " + (isBorrowed == true ? "已借出" :"未借出") +
'}';
}
}
BookList类
package book;
public class BookList {
private Book[] books = new Book[10];
private int useSized = 0;
public BookList(){
this.books[0] = new Book("三国演义","罗贯中",15,"小说");
this.books[1] = new Book("西游记","吴承恩",14,"小说");
this.books[2] = new Book("红楼梦","曹雪芹",15,"小说");
this.useSized = 3;
}
public int getUseSized() {
return useSized;
}
public void setUseSized(int useSized) {
this.useSized = useSized;
}
public Book getBook(int pos) {
return books[pos];
}
public void setBook(int pos,Book book) {
this.books[pos] = book;
}
public Book[] getBooks(){
return books;
}
}
opera包
IOperation接口
public interface IOperation {
void work(BookList bookList);
}
AddIOperation类
package opera;
import book.Book;
import book.BookList;
import java.util.Scanner;
public class AddIOperation implements IOperation{
@Override
public void work(BookList bookList) {
//1.判满
int currentSize = bookList.getUseSized();
if(currentSize == bookList.getBooks().length){
System.out.println("书放满了");
}
//2.插入
System.out.println("新增图书...");
System.out.println("请输入书名：");
Scanner sc = new Scanner(System.in);
String name = sc.nextLine();
System.out.println("请输入作者：");
String autor = sc.nextLine();
System.out.println("请输入价格：");
Scanner sc1 = new Scanner(System.in);
int price = sc1.nextInt();
System.out.println("请输入类型：");
String type = sc.nextLine();
Book newbook = new Book(name,autor,price,type);
//3.判断书架有没有这本书
for (int i = 0; i < currentSize; i++) {
Book book = bookList.getBook(i);
if(book.getName().equals(name)){
System.out.println("书架里有这本书,不能插入");
return;
}
}
//4.插入这本书
bookList.setBook(currentSize,newbook);
bookList.setUseSized(currentSize + 1);
System.out.println("新增图书成功");
}
}
BorroweIOperation类
package opera;
import book.Book;
import book.BookList;
import java.util.Scanner;
public class BorrowedIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("借阅图书...");
System.out.println("请输入要借阅的图书：");
Scanner sc = new Scanner(System.in);
String name = sc.nextLine();
int currentSize = bookList.getUseSized();
for (int i = 0; i < currentSize; i++) {
Book book = bookList.getBook(i);
if(book.getName().equals(name)){
if(book.isBorrowed() == true){
System.out.println("该图书已被借阅");
return;
}
book.setBorrowed(true);
System.out.println("借阅成功");
return;
}
}
System.out.println("没有你要借阅的图书");
}
}
DelIOperation类
package opera;
import book.Book;
import book.BookList;
import java.util.Scanner;
public class DelIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("删除图书...");
System.out.print("请输入要删除的图书：");
Scanner sc = new Scanner(System.in);
String name = sc.nextLine();
int currentSize = bookList.getUseSized();
int pos = -1;//pos用来记录找到图书的下标
//1.找到这本书
int i = 0;
for (; i < currentSize; i++) {
Book book = bookList.getBook(i);
if(book.getName().equals(name)){
pos = i;
break;
}
}
if(i == currentSize){
System.out.println("没有你要删除的图书");
return;
}
//2.开始删除图书
for (int j = pos; j < currentSize - 1; j++) {
//j < currentSize - 1,如果只是currentSize,会越界
//bookList[j] = bookList[j+1];
Book book = bookList.getBook(j+1);//创建一个book对象，里面放book【j+1】
bookList.setBook(j,book);
}
bookList.setUseSized(currentSize -1);
System.out.println("删除成功");
}
}
ExitIOperation类
package opera;
import book.Book;
import book.BookList;
public class ExitIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("退出系统...");
System.exit(0);
}
}
FindIOperation类
package opera;
import book.Book;
import book.BookList;
import java.util.Scanner;
public class FindIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("查阅图书...");
System.out.println("输入要查找的图书：");
Scanner sc = new Scanner(System.in);
String name = sc.nextLine();
int currentSize = bookList.getUseSized();
for (int i = 0; i < currentSize; i++) {
Book book = bookList.getBook(i);
if(book.getName().equals(name)){
System.out.println("有这本书");
System.out.println(book);
return;
}
}
System.out.println("没有找到这本书");
}
}
ReturnIOperation类
package opera;
import book.Book;
import book.BookList;
import java.util.Scanner;
public class ReturnIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("归还图书...");
System.out.println("请输入你要归还的图书：");
Scanner sc = new Scanner(System.in);
String name = sc.nextLine();
int currentSize = bookList.getUseSized();
for (int i = 0; i < currentSize; i++) {
Book book = bookList.getBook(i);
if(book.getName().equals(name)){
if(book.isBorrowed() == false){
System.out.println("该图书未被借阅，不能归还");
return;
}
book.setBorrowed(false);
System.out.println("归还成功");
}
}
}
}
ShowIOperation类
package opera;
import book.Book;
import book.BookList;
public class ShowIOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("显示图书...");
int currentSize =bookList.getUseSized();
for (int i = 0; i < currentSize; i++) {
Book book = bookList.getBook(i);
System.out.println(book);
}
}
}
use包
User类
package use;
import book.BookList;
import opera.IOperation;
public abstract class User {
protected String name;
public IOperation[] iOperations;
public User(String name) {
this.name = name;
}
public abstract int meun();
public void doIOperation(int choice, BookList bookList){
iOperations[choice].work(bookList);
}
}AdminUser类
package use;
import opera.*;
import java.util.Scanner;
public class AdminUser extends User{
public AdminUser(String name) {
super(name);
this.iOperations = new IOperation[]{
new ExitIOperation(),
new FindIOperation(),
new AddIOperation(),
new DelIOperation(),
new ShowIOperation()
};
}
@Override
public int meun() {
System.out.println("**********");
System.out.println("1.查找图书");
System.out.println("2.新增图书");
System.out.println("3.删除图书");
System.out.println("4.显示图书");
System.out.println("0.退出系统");
System.out.println("**********");
System.out.println("请输入需要的操作：");
Scanner sc = new Scanner(System.in);
int choice = sc.nextInt();
return choice;
}
}
NormalUser类
package use;
import opera.*;
import java.util.Scanner;
public class NormalUser extends User{
public NormalUser(String name) {
super(name);
this.iOperations = new IOperation[]{
new ExitIOperation(),
new FindIOperation(),
new BorrowedIOperation(),
new ReturnIOperation()
};
}
@Override
public int meun() {
System.out.println("**********");
System.out.println("1.查找图书");
System.out.println("2.借阅图书");
System.out.println("3.归还图书");
System.out.println("0.退出系统");
System.out.println("**********");
System.out.println("请输入需要的操作：");
Scanner sc = new Scanner(System.in);
int choice = sc.nextInt();
return choice;
}
}
这里是小川，祝你开心，不止今天。
