Question

java中显示错误需要标识符是什么意思？

class Cuboid{ private double length; private double width; private double high; private double s1; private double s2; private double s3;
s1=length*width*high; void volume() { System.out.println(s1); } }class CuboidWeight extends Cuboid{ double density; s2=length*width*high*density; void weight() { System.out.println(s2); }}class CuboidValue extends CuboidWeight{ double value;s3=length*width*high*density*value; void none() { System.out.println(s3); }}class Demo333{ public static void main(String[] args) { Cuboid cu=new Cuboid(); cu.volume(1.1,1.1,1.1); CuboidWeight cub=new CuboidWeight(); cub.weight(1.1,1.1,1.1,1.1); CuboidValue cubo=new CuboidValue(); cubo. none(1.1,1.1,1.1,1.1,1.1); System.out.println(s1); System.out.println(s2); System.out.println(s3); }}

刚学，勿喷。。。。

Answer 1

这几个类是写在一起的还是?
每个类应该都是有构造方法的或者volume，weight这几个方法是要传参数的，但是你的方法是没有传参

追问

oo ，那能不能帮我解答一下那个需要标识符的问题呢？我正在修改中。。。

追答

写的地方不对，因为后面那几个参数都没有定义，感觉这里应该有一个构造方法

Answer 2

s1=length*width*high;运算要放到方法体内,还有属性私有化之后不能被继承,除了Cuboid类本身，其他类都没法直接访问到

Answer 3

你把属性设置为私有的 不能继承

Answer 4

public class Cuboid
{
protected double length;
protected uble width;
protected double high;
protected ouble s1;
protected double s2;
protected ouble s3;

publc void volume()
{
s1=length*width*high;
System.out.println(s1);

}

}
public class CuboidWeight extends Cuboid
{
prodected double density;

public void weight()
{
s2=length*width*high*density;
System.out.println(s2);

}
}
public class CuboidValue extends CuboidWeight
{
double value;

public void none()
{
s3=length*width*high*density*value;
System.out.println(s3);

}
}
class Demo333
{
public static void main(String[] args)
{
length=1;
width =2;
high=3;
density=4;
value=5;
CuboidValue cubo=new CuboidValue();
cubo.volume();
cucuboeight();
cubo. none();
}
}