BMS
- 2. 书架储存书【bookList】
- 初始化书架,类构造方法getBook,拿出pos处的书setBook,给pos下标放一本书getUesSize,setUesSize,获取实时书本数,用于修改
- 3. 设置两个角色【user】
- 构造方法,提供构造方法帮助父类构造构造方法,提供构造方法帮助父类构造
- 4. 每个角色对应功能列表不一样
- 5. 实现每一具体功能【operation】
- 功能标准化【IOperation】增添图书【AddOperation】借阅图书【BorrowOperation】删除图书【DelOperation】显示图书【DisplayOperation】归还图书【ReturnOperation】查找图书【FindOperation】退出系统【ExitOperation】
项目实现
创几个包:用来组织类(分类)
1. 每本书数据【book】
public class Book {
}
设置字段(书的属性)
public class Book {
private String name; //书名
private String author; //作者
private int price; //价格
private String type; //类型
private boolean isBorrowed;//是否被借出 默认false
提供构造
实例化对象,设置几个属性,因为字段是private修饰的就给每属性get set方法
在加个构造和toString方法
//构造
public Book(String name, String author, int price, String type) {
this.name = name;
this.author = author;
this.price = price;
this.type = type;
}
get+set方法,便于操作数据
//get+set
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 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;
}
重写toString方法,便于打印显示,(借出处略加修改)
//toString
@Override
public String toString() {
return "Book{" +
"name='" + name + ''' +
", author='" + author + ''' +
", price=" + price +
", type='" + type + ''' +
((isBorrowed==true)?"已经借出":"未借出") +
'}';
}
2. 书架储存书【bookList】
BookList类
public class BookList{
}
设置书架大小
//对多放十本
private Book[] books = new Book[3];
private int usedSize ; //实时记录 目前有几本书
初始化书架,类构造方法
public BookList() {
books[0] = new Book("西游记","吴承恩",10,"小说");
books[1] = new Book("三国演义","施耐庵",11,"小说");
books[2] = new Book("红楼梦","曹雪芹",12,"小说");
usedSize = 3;
}
getBook,拿出pos处的书
//拿出pos处的书
public Book getBook(int pos){
return books[pos];
}
setBook,给pos下标放一本书
// 给pos下标放一本书
public void setBook(int pos, Book book){
books[pos] = book;
}
getUesSize,setUesSize,获取实时书本数,用于修改
//获取实时书本数,用于修改
public int setUesSize(int size){
return (usedSize = size);
}
public int getUesSize(){
return this.usedSize;
}
3. 设置两个角色【user】
管理员【AdmainUser】
public class AdmainUser extends User{
}
构造方法,提供构造方法帮助父类构造
//提供构造方法帮助父类构造
public AdmainUser(String name) {
super(name);
//在new管理人员这个对象时,就把这些功能一并写入
this.iOperations = new IOperation[]{
new ExitOperation(),//0
new FindOperation(),
new AddOperation(),
new DelOperation(),
new DisplayOperation()
};
//设置一个开始菜单
public int menu (){
System.out.println("hello"+this.name+"欢迎使用BMS!");
System.out.println("1.查找图书");
System.out.println("2.增添图书");
System.out.println("3.删除图书");
System.out.println("4.显示图书");
System.out.println("0.退出BNS");
Scanner scanner = new Scanner(System.in);
return scanner.nextInt();
}
普通用户【NormalUser】
public class NormalUser extends User{
}
菜单【menu】
//设置一个开始菜单
public int menu (){
System.out.println("hello"+this.name+"欢迎使用BMS!");
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BNS");
Scanner scanner = new Scanner(System.in);
return scanner.nextInt();
}
构造方法,提供构造方法帮助父类构造
//提供构造方法帮助父类构造
public NormalUser(String name) {
super(name);
//在new一般人员这个对象时,就把这些功能一并写入
this.iOperations = new IOperation[]{
new ExitOperation(),//0
new FindOperation(),
new BorrowOperation(),
new ReturnOperation()
};
}
4. 每个角色对应功能列表不一样
身份不同,拥有的功能不一样
管理员 |
一般用户 |
1.查找图书 |
1.查找图书 |
2.增添图书 |
2.借阅图书 |
3.删除图书 |
3.归还图书 |
4.显示图书 |
|
0.退出BNS |
0.退出BNS |
5. 实现每一具体功能【operation】
接口【interface】
功能标准化【IOperation】
public interface IOperation {
//实现功能
public abstract void work(BookList bookList);
}
增添图书【AddOperation】
- implements实现接口
- 录入书本信息
- 用getUesSize(),在书架的size位置插入这本书
Tips:
要先输入字符串String,再输入整数int!
先输入整数再输字符串的话回车会被读进去
package operation;
import book.Book;
import book.BookList;
import java.util.Scanner;
public class AddOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("添加图书!");
Scanner scanner = new Scanner(System.in);
System.out.println("请输入图书的名字");
String name = scanner.nextLine();
System.out.println("请输入图书的作者");
String author = scanner.nextLine();
System.out.println("请输入图书的类型");
String type = scanner.nextLine();
System.out.println("请输入图书的价格");
int price = scanner.nextInt();
Book newbook = new Book(name,author,price,type);
bookList.setBook(bookList.getUesSize(),newbook);
bookList.setUesSize(bookList.getUesSize()+1); //更新数量
System.out.println("新增书记成功!");
}
}
借阅图书【BorrowOperation】
package operation;
import book.Book;
import book.BookList;
import java.util.Scanner;
public class BorrowOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("借出图书!");
System.out.print("请输入借阅图书的名字:");
int currentSize = bookList.getUesSize();
Scanner scanner = new Scanner(System.in);
String name = scanner.nextLine();
for (int i = 0 ; i < currentSize; i++) {
Book book = bookList.getBook(i);
if (book.getName().equals(name)) {
System.out.println("找到了!");
book.setBorrowed(true); //改状态
System.out.println("借阅成功!");
return;
}
}
System.out.println("没有这本书!");
System.out.println();
}
}
删除图书【DelOperation】
package operation;
import book.Book;
import book.BookList;
import java.util.Scanner;
/**
*覆盖
*/
public class DelOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("删除图书!");
System.out.print("请输入图书的名字:");
int currentSize = bookList.getUesSize();
Scanner scanner = new Scanner(System.in);
String name = scanner.nextLine();
int index = -1;//存下标
int i = 0;
for ( ; i < currentSize; i++) {
Book book = bookList.getBook(i);
if (book.getName().equals(name)) {
System.out.println("找到了!");
index = i;
System.out.println(book);
System.out.println();
}
}
if (i >= currentSize) {
System.out.println("找不到此书");
return;
}
//直接覆盖
for (int j = index; j < currentSize-1; i++) {
bookList.setBook(j,bookList.getBook(j +1));
}
bookList.setUesSize(bookList.getUesSize()-1); //更新数量
bookList.setBook(currentSize-1,null); //置为空 相当于free
System.out.println("删除成功!");
System.out.println();
}
}
显示图书【DisplayOperation】
package operation;
import book.BookList;
public class DisplayOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("显示图书!");
int currentSize = bookList.getUesSize();
for (int i = 0; i < currentSize; i++) {
System.out.println(bookList.getBook(i));
}
System.out.println();
}
}
归还图书【ReturnOperation】
package operation;
import book.Book;
import book.BookList;
import java.util.Scanner;
public class ReturnOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("归还图书!");
System.out.print("请输入归还图书的名字:");
int currentSize = bookList.getUesSize();
Scanner scanner = new Scanner(System.in);
String name = scanner.nextLine();
for (int i = 0 ; i < currentSize; i++) {
Book book = bookList.getBook(i);
if (book.getName().equals(name)) {
System.out.println("找到了!");
book.setBorrowed(true); //改状态
System.out.println("归还成功!");
return;
}
}
System.out.println("没有这本书!");
System.out.println();
}
}
查找图书【FindOperation】
package operation;
import book.Book;
import book.BookList;
import java.util.Scanner;
public class FindOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.print("请输入图书的名字:");
int currentSize = bookList.getUesSize();
Scanner scanner = new Scanner(System.in);
String name = scanner.nextLine();
for (int i = 0 ; i < currentSize; i++) {
Book book = bookList.getBook(i);
if (book.getName().equals(name)) {
System.out.println("找到了!");
System.out.println(book);
System.out.println();
return;
}
}
System.out.println("没有这本书!");
System.out.println();
}
}
退出系统【ExitOperation】
package operation;
import book.BookList;
public class ExitOperation implements IOperation{
@Override
public void work(BookList bookList) {
System.out.println("退出系统!");
System.exit(0); // 状态码 零代表正常结束,负数异常结束
}
}
6. 主函数 【Main】
整理所有功能
import book.Book;
import book.BookList;
import user.AdmainUser;
import user.NormalUser;
import user.User;
import java.util.Scanner;
//登录
public class Main {
public static User login(){
System.out.println("请输入你的姓名:");
Scanner scanner = new Scanner(System.in);
String name = scanner.nextLine();
System.out.println("请输入你的身份: 1-->管理员,2-->普通用户");
int choise = scanner.nextInt();
if(choise == 1){
return new AdmainUser(name);
}else {
return new NormalUser(name);
}
}
public static void main(String[] args) {
//整合!
BookList bookList = new BookList();//准备图书
//登录,
User user = login();
while(true) {
int choise = user.menu();//父类的引用想访问子类的方法,此方法必须为抽象方法,动态绑定
user.doOperator(choise, bookList);
}
}
}
率7. 总结
我亦无他,惟手熟尔!,多动手实操!在实践中进步!
原文链接: