package zuoye8;
public abstract class Shape {
private double zhouchang ;
private double mianji ;
public Shape(double zhouchang, double mianji) {
super();
this.zhouchang = zhouchang;
this.mianji = mianji;
}
public Shape() {
super();
}
//抽象一个周长方法
public double zhouchang ()
{
return zhouchang;}
}
package zuoye8;
public class Juxing extends Shape {
private double c;
private double d;
public Juxing( double c, double d) {
super();
this.c = c;
this.d = d;
}
@Override
public double zhouchang() {
double zhouchang ;
zhouchang =(c+d)*2;
return zhouchang ;
}
}
package zuoye8;
public class Sanjaio extends Shape {
//三角形三边属性
private double a;
private double b;
private double c;
public Sanjaio( double a, double b, double c) {
super();
this.a = a;
this.b = b;
this.c = c;
}
public Sanjaio() {
}
//周长
public void
zhouchang (double a,double b,double c)
{
if(a+b>c&&Math.abs(a-b)<c)//绝对值，保证是正整数
{
double zhouchang ;
System.out.println(zhouchang =a+b+c);
}
else
{
System.out.println("这不是三角形");
}
}
}
package zuoye8;
public class E {
public static void main(String[] args) {
Juxing j=new Juxing(3,4);
System.out.println("长=4，宽=3的矩形周长="+j.zhouchang());
Sanjaio s=new Sanjaio();
System.out.println( "边分别是3,4,5的三边形周长是：");
s.zhouchang(3, 4, 5);
s.zhouchang(3,1,5);
}
}