Java超类toString（）和构造函数调用

Java super class toString() and constructor calling

我知道有类似的帖子，但没有一个完全适合我想做的。我是一个更新的程序员，刚刚开始阅读Java的超级类。我已经创建了一个名为shape的超级类。然后我创建了一个名为circle的子类。我在这里遇到了两个困难，从我的子类ToString方法调用我的父类中的ToString方法，以及从我的子类到我的超类中的一个构造函数。我在下面提供了我的超级类、子类和主要测试方法。

形状类：

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public class Shape
{
private boolean isFilled;
private String color;

public Shape()
{
this.isFilled = true;
this.color ="Green";

}

public Shape(boolean x, String y)
{
this.isFilled = x;
this.color = y;
}

public void setFilled(boolean fill)
{
this.isFilled = fill;
}

public boolean getFilled()
{
return this.isFilled;
}

public void setColor(String x)
{
this.color = x;
}

public String getColor()
{
return this.color;
}

@Override
public String toString()
{
String s ="Filled:" + this.isFilled +"
";
String t ="Color:" + this.color;
String u = s + t;

return u;

}
}

圆圈：

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public class Circle extends Shape
{
private double radius;

public Circle()
{
this.radius = 1;
}

public Circle(double x)
{
this.radius = x;
}

public Circle(double radius, boolean isFilled, String Color)
{
super(isFilled, Color);
this.radius = radius;

}

public void setRadius(double radius)
{
this.radius = radius;
}

public double setRadius()
{
return this.radius;
}

public double getArea()
{
double area = this.radius * this.radius * Math.PI;

return area;
}

@Override
public String toString()
{

String x ="Radius:" + this.radius +"
";
String y ="Area:" + getArea() +"
";

String z = x + y;
return z;

}
}

号

测试形状：

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

Circle c1 = new Circle(2.67);
System.out.println("c1:");
System.out.println(c1.toString());
System.out.println();

Circle c2 = new Circle(3, false,"Red");
System.out.println("c2:");
System.out.println(c2.toString());
System.out.println();
}
}

预期输出：

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c1:
Radius: 2.67
Area: 22.396099868176275
Filled: true
Color: Green

c2:
Radius: 3.0
Area: 28.274333882308138
Filled: false
Color: Red

。

实际输出：

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c1:
Radius: 2.67
Area: 22.396099868176275

c2:
Radius: 3.0
Area: 28.274333882308138