我试图运行一个程序,如果一切顺利,能够花一年时间并返回当年发布的专辑的标题。我已经给了它6张专辑,现在我正在试图打印一个标题。我修复了一些令人沮丧的错误,但这是我以前从未见过的错误。错误出现在第21行,但我不确定它的含义。谁能帮忙?“线程中的异常”main“java.lang.NullPointerException”
package songselector;
import java.util.Scanner;
public class Main {
public class Album
{
int year; String title;
public Album() {
this.year = 0; this.title = null;
}
public Album (int year, String title) {
this.year = year; this.title = title;
}
}
class CAKE {
Album[] albums;
public CAKE() {
albums = new Album[6];
albums[0].year = 1994; albums[0].title = "Motorcade Of Generosity";
albums[1].year = 1996; albums[1].title = "Fashion Nugget";
albums[2].year = 1998; albums[2].title = "Prolonging The Magic";
albums[3].year = 2001; albums[3].title = "Comfort Eagle";
albums[4].year = 2004; albums[4].title = "Pressure Chief";
albums[5].year = 2011; albums[5].title = "Showroom of Compassion";
}
public void printAlbum (int y) {
System.out.println (albums[y].title);
}
}
public static void main(String[] args) {
new Main().new CAKE().printAlbum (0);
}
}
它是'专辑[0]',并且使用他的ctor它可以是'albums [0] =新专辑(1994,“Motorcade Of Generosity”);' – entonio 2011-05-11 00:53:43
oops ...将编辑。谢谢! – MByD 2011-05-11 00:54:49
啊,好吧。谢谢你,这很有道理。现在运行良好。 – James 2011-05-11 01:00:52