关于java的一个问题
package hello;
import java.math.*;
public class AAA {
public static void main(String args[]) {
Trangle tra=new Trangle();
tra.SetTrangle(3, 4, 5);
boolean flag=tra.IsTrangle();
if(flag) {
System.out.println("可以构成三角形");
System.out.println("三角形的周长为:"+tra.GetLength());
System.out.println("三角形的面积为:"+tra.GetArea());
}
else System.out.println("不能构成三角形");
Lader lad=new Lader();
lad.SetLader(2,3,4);
System.out.println("梯形的面积为:"+lad.GetArea());
Circle cir=new Circle();
cir.SetCircle(2);
System.out.println("圆的周长为:"+cir.GetLength());
System.out.println("圆的面积为:"+cir.GetArea());
}
}
class Trangle{
private double a,b,c;
private double length;
private double area;
public void SetTrangle(double aa,double bb,double cc) {
a=aa;b=bb;c=cc;
}
public double GetLength(){
length=a+b+c;
return length;
}
public double GetArea() {
double p=(a+b+c)*0.5;
area=Math.sqrt(p*(p-a)*(p-b)*(p-c)); //海伦公式求三角形面积
return area;
}
public boolean IsTrangle() {
return a+b>c&&a+c>b&&b+c>a&&a-b<c&&a-c<b&&b-c<a;
}
}
class Lader{
private double upbase;
private double downbase;
private double height;
private double area;
public void SetLader(double ub,double db,double h) {
upbase=ub;
downbase=db;
height=h;
}
public double GetArea() {
area=(upbase+downbase)*height*0.5;;
return area;
}
}
class Circle{
private double radius;
private double length;
private double area;
public void SetCircle(double r) {
radius=r;
}
public double GetLength() {
final double PI=3.14f;
length=2*PI*radius;
return length;
}
public double GetArea() {
final double PI=3.14f;
area=PI*radius*radius;
return area;
}
}
类中的赋值方法的语句为什么不能写到一行用逗号隔开?写到一行就报错,分开每条语句就不会报错,求解答。