Book, BookUtils, BookPrinter, BookApp(2), MethodOverloading(App).java

public class Book {
    // 필드
    // 제목, 저자, 출판사, 가격, 출판일, 절판 여부

    String title;
    String writer;
    String publisher;
    int price;
    int pubDate;
    boolean sell;
}

 

public class BookUtils {
    // Book 객체 하나를 전달받아서 책 정보를 출력하는 기능
    void printBook(Book book) {
        System.out.println("제    목: " + book.title);
        System.out.println("저    자: " + book.writer);
        System.out.println("출 판 사: " + book.publisher);
        System.out.println("가    격: " + book.price);
        System.out.println("출 판 일: " + book.pubDate);
        System.out.println("판매여부: " + book.sell);
        System.out.println("=======================================");
    }


    // Book 배열을 전달받아서 판매하지 않는 책만 출력하는 기능
    void printBookForSell(Book[] books) {
        for (Book book : books) {
            if (!book.sell == true) {
                printBook(book);
            }
        }
    }


    // Book 배열을 전달받아서 가장 비싼 책(Book)을 제공하는 기능
    Book getExpensiveBook(Book[] books) {
        Book expensiveBook = null;

        int expensivePrice = 0;
        for (Book book : books) {
            if (expensivePrice < book.price) {
            expensivePrice = book.price;
            expensiveBook = book;
            }
        }
        return expensiveBook;
    }
}

 

public class BookPrinter {
    void displayBook(Book book) {
        System.out.println("제    목: " + book.title);
        System.out.println("저    자: " + book.writer);
        System.out.println("출 판 사: " + book.publisher);
        System.out.println("가    격: " + book.price);
        System.out.println("출 판 일: " + book.pubDate );
        System.out.println("판매여부: " + book.sell);

        BookPrinter print = new BookPrinter();

    }
}

 

public class BookApp {
    public static void main(String[] args) {
        // Book 객체 생성 후 책 정보 저장 및 출력하기
        Book b1 = new Book();

        b1.title = "잃어버린 시간을 찾아서";
        b1.writer = "마르셀 프루스트";
        b1.publisher = "비상";
        b1.price = 10000;
        b1.pubDate = 19901023;
        b1.sell = true;

        BookPrinter printer = new BookPrinter();
        printer.displayBook(b1);


    /*  System.out.println(b1.name);
        System.out.println(b1.writer);
        System.out.println(b1.price);
        System.out.println(b1.publishdate);
        System.out.println(b1.sale);
         */
    }
}

 

public class BookApp2 {
    public static void main(String[] args) {
        Book[] books = new Book[3];

        Book book1 = new Book();
        book1.title = "이것이 자바다";
        book1.writer = "신용권";
        book1.publisher = "한빛";
        book1.price = 30000;
        book1.pubDate = 20190228;
        book1.sell = true;

        Book book2 = new Book();    
        book2.title = "자바의 정석";
        book2.writer = "남궁성";
        book2.publisher = "강산북스";
        book2.price = 27000;
        book2.pubDate = 20190101;
        book2.sell = true;

        Book book3 = new Book();
        book3.title = "메롱";
        book3.writer = "메롱의 저자";
        book3.publisher = "메롱의 출판사";
        book3.price = 12345;
        book3.pubDate = 20190301;
        book3.sell = false;


        books[0] = book1;
        books[1] = book2;
        books[2] = book3;

        BookUtils util = new BookUtils();
        System.out.println("----책 정보 출력 기능----");
        util.printBook(book1);
        util.printBook(book2);
        util.printBook(book3);

        System.out.println("----판매하지 않는 책 출력 기능----");
        util.printBookForSell(books);

        System.out.println("----가장 비싼 책 획득하기----");
        Book b = util.getExpensiveBook(books);
        util.printBook(b);
    }
}

 

public class MethodOverloading {
    void m() {
        System.out.println("매개변수 없는 m()이 실행됨");
    }    
    void m(int a) {
        System.out.println("int m()이 실행됨");
    }
    void m(int a, int b) {
        System.out.println("m(int a, int b)이 실행됨");
    }
    void m(String a) {
        System.out.println("m(String a)이 실행됨");
    }
}

 

public class MethodOverloadingApp {
    public static void main(String[] args) {
        MethodOverloading x = new MethodOverloading();

        x.m();
        x.m(20);
        x.m(20, 30);
        x.m("홍길동");
    }
}