JAVA继承类求几何图形面积周长代码

System.out.println("三角形面积"+t.getArea());
rectangle r=new rectangle(4,5);
System.out.print("矩形"+t.toString());
}
class shap2D
{
static double getArea; //面积
static double getPerimeter; //周长
}
class circle extends shap2D
{
double r;
double getRadius(){return r=2;}
double getArea() {return Math.PI*r*r;}
public double getArea()
{
double s=(a+b+c)/2;
return Math.sqrt(s*(s-a)*(s-b)*(s-c));
}
public boolean isTriangle()
{
boolean flag=false;
if(a>0&&b>0&&c>0&&a+b>c&&a+c>b&&c+b源自文库a)
flag=true;
return flag;
}
}
class rectangle extends circle
{
double a,b;
rectangle(double x,double y)
{a=x; b=y;}
void setA(double x){a=x;}
double getA(){return a;}
{
double a,b,c;
Triangle (double x,double y,double z)
{a=x; b=y;c=z;}
void setA(double x){a=x;}
double getA(){return a;}
public double getPerimeter() {return a+b+c;}
System.out.println("圆的的半径"+c1.getRadius()+c1.toString());
Triangle t=new Triangle(3,4,5);
System.out.println("三角形周长："+t.getPerimeter());
if(t.isTriangle())
public double getPerimeter() {return 2*(a+b);}
public double getArea(){return a*b;}
}
public class Shap
{
public static void main(String args[])
{
circle c1=new circle();
double getPerimeter() {return 2*Math.PI*r;}
public String toString()
{
String s;
return s="周长："+getPerimeter()+"面积:"+getArea();
}
}
class Triangle extends circle