为什么这个文件编译后出现了三个.class文件?
class Art
{
Art()
{
System.out.println("Art");
}
}
class Art2 extends Art
{
Art2()
{
System.out.println("Art2");
}
}
public class Art3 extends Art2
{
Art3()
{
System.out.println("Art3");
}
public static void main(String[] args)
{
Art3 a=new Art3();
}
}