理解Java的Class类、"this."关键字、Constructor构造器（一）

import java.util.*;

public class BookTest

{

	public static void main(String[] args)

	{

		//Book book = new Book("A Tale of Two Cities", 1895);

		Book book = new Book("A Tale of Two Cities");

		System.out.println(book.title);

		System.out.println(book.pubYear);

		System.out.println(Book.count);

		Book book2 = new Book("War and Peace");

		System.out.println(Book.count); // count 是静态变量，新建book2实类后自动+1

	}

}

class Book

{

	String title;

	int pubYear;

	static int count = 0;

	public Book(String title)

	{

		this(title, -1); //如果没有接收到第二个变量，pubYear自动设为1

	}

	public Book(String title, int pubYear)

	{

		setTitle(title);

		setPubYear(pubYear);

		++count;

	}

	public void setTitle(String title)

	{

		this.title = title;

	}

	public void setPubYear(int pubYear)

	{

		this.pubYear = pubYear;

	}

}

巴特西

理解Java的Class类、"this."关键字、Constructor构造器（一）

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