我正在尝试解决这个问题:
一本书,作为标题,作者和出版年份。包括获取和设置私有实例变量的方法以及用于显示对象的toString方法。还要创建一个方法moreRecent,它将两本书作为输入参数,并返回最近发布的一本书。为moreRecent创建3个JUnit测试。
但是,我不知道如何访问其他私有实例变量author和yearofPub。我每个类只能做一个构造函数吗?那么如何获得其他2个变量呢?到目前为止这是我的代码: 谢谢!
class Book {
private String title;
private String author;
private String yearofPub;
Book(String input) {
title = input;
}
String moreRecent(int Book1, int Book2) {
String moreRecent;
if(Book1 > Book2) {
moreRecent = "Book 1";
}
if (Book2 > Book1) {
moreRecent = "Book 2";
}
else
moreRecent = "Both";
return moreRecent;
}
}
public class Chpt2930BookTitleAuthorYear {
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
System.out.println("Enter title of Book: ");
String nextLine = scan.next();
Book titleofBook = new Book(nextLine);
}
}
EDIT --------------------------
好的,谢谢你的回复! 我进一步改进了我的代码,但仍然无法得到正确的结果。我特别难以使用moreRecent方法。如何为这些书设置yearofPub?这是我的代码:
class Book {
private String title;
private String author;
private String yearofPub;
Book(String input) {
title = input.toString();
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
public String getYearofPub() {
return yearofPub;
}
public void setYearofPub(String yearofPub) {
this.yearofPub = yearofPub;
}
public String toString() {
System.out.println("Book{" + "Title=" + title + " Author=" + author + " Year of
Publication=" + yearofPub + "}");
return " ";
}
//confused on this part :(
String moreRecent(Book Book1, Book Book2) {
if (Book1.getYearofPub>Book.getYearofPub) { //Is this correct? I'm not sure :/
}
}
}
public class Chpt2930BookTitleAuthorYear {
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
System.out.println("Enter title of Book: ");
String nextLineTitle = scan.nextLine();
Book titleofBook = new Book(nextLineTitle);
System.out.println("Enter author of the Book: ");
String nextLineAuthor = scan.nextLine();
titleofBook.setAuthor(nextLineAuthor);
System.out.println("Enter the date of publication of the Book: ");
String nextLineDate = scan.nextLine();
titleofBook.setYearofPub(nextLineDate);
titleofBook.toString();
}
}
谢谢!
编辑2 -----------------
Nvm'd我发现了问题:) 感谢您提供的所有帮助
答案 0 :(得分:2)
这样做:
class Book {
private String title;
private String author;
private String yearofPub;
Book(String input) {
title = input;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
public String getYearofPub() {
return yearofPub;
}
public void setYearofPub(String yearofPub) {
this.yearofPub = yearofPub;
}
}
在您的主要方法中,您可以:
Book titleofBook = new Book(nextLine);
titleofBook.setAuthor(...)
答案 1 :(得分:1)
为变量提供所谓的访问器。例如:
public String getAuthor() {
return this.author;
}
public void setAuthor(String author) {
this.author = author;
}
同样适用于yeaofPub
字段。