问下关于继承的问提

Question

abstract class shape
{
public abstract void square();
}
class shape1 extends shape{
float bianchang=3.14;
public void square()
{
System.out.println( bianchang*bianchang);
}}
class shape2 extends shape{
float bianchang=3.14;
float kuangdu=9.6;
public void square()
{
System.out.println( bianchang*kuangdu*bianchang);
}}
public class Test
{
public static void main(String[] args)
{
shape A=new shape1;
shape B=new shape2;
square(shape A);
square(shape B); }
}
我想学java 可是为什么 不能够编译成功

Answer 1

square(shape A)和square(shape B) 改为A.square()和B.square() 你试试

Answer 2

将你代码修改为如下：
abstract class shape
{
    public abstract void square();
}
class shape1 extends shape{
    float bianchang=3.14f;
    public void square()
    {
        System.out.println( bianchang*bianchang);
    }}
class shape2 extends shape{
    float bianchang=3.14f;
    float kuangdu=9.6f;
    public void square()
    {
        System.out.println( bianchang*kuangdu*bianchang);
    }
}public class Test
{
    public static void main(String[] args)
    {
        shape A=new shape1();
        shape B=new shape2();
        A.square();
        B.square();
    }
}

Answer 3

float bianchang=3.14;
3.14默认是double类型的，要是标志是float要在后面加上f  或  F

Answer 4

改成
         shape A=new shape1();
        shape B=new shape2();
        A.square();
        B.square();
另外