一个简单的java程序设计问题，小白求教，急求

建立商店类和书类

书
拥有价格 作者 书名
构建三个单独方法获取书的价格 作者和书名

商店
拥有三本书（尝试使用数组）
书名 价格 作者分别是
Java 80 sipc
Android 40 jiang
JavaWeb 40 wang
分别构建查询价格及作者方法 参数为书名 返回价格及作者

在主函数中调用输入书名 分别调用两个查询方法 分别输出返回值

1.建两个类，Book类和Store类，类名和文件名保持一致
2.运行Store类的main方法即可：
=========================1.Book类====================

package sn.test;

public class Book {
    //作者
    private String bookWirter;
    //书名
    private String bookName;
    //书价格
    private Double bookPrice;

    /***
     * 空的构造函数
     */
    public Book() {
    }

    /**
     * 带参数的构造函数
     * @param bookWirter
     * @param bookName
     * @param bookPrice
     */
    public Book(String bookWirter, String bookName, Double bookPrice) {
        this.bookWirter = bookWirter;
        this.bookName = bookName;
        this.bookPrice = bookPrice;
    }

    public String getBookWirter() {
        return bookWirter;
    }

    public void setBookWirter(String bookWirter) {
        this.bookWirter = bookWirter;
    }

    public String getBookName() {
        return bookName;
    }

    public void setBookName(String bookName) {
        this.bookName = bookName;
    }

    public Double getBookPrice() {
        return bookPrice;
    }

    public void setBookPrice(Double bookPrice) {
        this.bookPrice = bookPrice;
    }
}

=============================Store类=======================
package sn.test;
import  sn.test.Book;

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class Store {
    private static List<Book> bookList;

    public Store() {
        bookList=new ArrayList<Book>();
        bookCheckIn("sipc","java",80.00);
        bookCheckIn("jiang","Android",40.00);
        bookCheckIn("wang","JavaWeb",40.00);
    }
    public  void bookCheckIn(String bookWriter,String bookName,Double bookPrice){
        Book book=new Book(bookWriter,bookName,bookPrice);
        this.bookList.add(book);
    }
    public static String searchBookWritter(String bookName){
        for (Book book :bookList){
            if(bookName.equals(book.getBookName().trim())){
                return book.getBookWirter();
            }
        }
        return null;
    }
    public static Double searchBookPrice(String bookName){
        for (Book book :bookList){
            if(bookName.equals(book.getBookName().trim())){
                return book.getBookPrice();
            }
        }
        return null;
    }
    public static void main(String [] args){
        Store store=new Store();
        while (true){
            System.out.println("请输入您要查询的书的名称:");
            Scanner sc=new Scanner(System.in);
            String bookName=sc.next();
            if (null!=bookName && !"".equals(bookName)){
                System.out.println("书的名称:"+bookName);
                String wirter=store.searchBookWritter(bookName);
                Double price=store.searchBookPrice(bookName);
                if (wirter!=null && price!=null){
                    System.out.println("书的作者:"+wirter);
                    System.out.println("书的价格:"+price);
                }
                else{
                    System.out.println("抱歉，没有查询到您要的书，请检查书名后再进行查询。。。");
                }

            }

        }
    }
}