Java编译错误:找不到符号

Question

嘿,我刚刚开始编写关于java的第一本编程书,所以这应该是一个简单的解决方案.用我对条件语的新知识搞清楚,我得到了标题错误.

这是代码:

import java.util.Scanner;

public class Music
{
    public static void main( String[] args )
    {

        Scanner x = new Scanner( System.in );

        int y;

        System.out.print( "Which is better, rap or metal? 1 for rap, 2 for metal, 3 for neither" );
        y = input.nextInt();

        if ( y == 1 )
            System.out.print( "Someone hasn't heard\nhttp://www.youtube.com/watch?v=Vzbc4mxm430\nyet" );

        if ( y == 2 )
            System.out.print( "Someone hasn't heard\nhttp://www.youtube.com/watch?v=s4l7bmTJ7j8\nyet" );

        if ( y == 3 )
            System.out.print( "=/ \nMusic sucks anyway." );
    }
}

当我尝试编译时:

Music.java:13: error: cannot find symbol
y = input.nextInt();



symbol: variable input
location: class Music
1 error

Answer 1

错误消息告诉您示波器中不存在您的变量"input".您可能想要使用Scanner对象,但是将其命名为"x",而不是"输入".

Scanner input = new Scanner( System.in );

应该解决它.

Answer 2

您尚未在input此处定义变量.你应该有:

Scanner input = new Scanner( System.in );