各位大佬们java中报错Syntax error on token "haha", ; expected after this token 如何解决呢？

Syntax error on token "haha", ; expected after this token

package haha
import java.util.Scanner;
public class Demo {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner scanner = new Scanner (System.in);
        System.out.print("请输入一个数");
        int a = scanner.nextInt();
        System.out.printf("%d的平方是%d\n",a,a*a);


    }
}

package haha
改为：
package haha;
包名后面加分号