java编程知道坐标求三角形做了一部分题目要求写出一个Point(点)类,该类具有x,y(表示点的横、纵坐标)两个属性,并定义两个构造方法,一个无参数,将x,y均设置为0,另一对坐标值为参数,设置x,y为

Question

java编程 知道坐标求三角形
做了一部分题目要求写出一个Point(点)类,该类具有x,y(表示点的横、纵坐标)两个属性,并定义两个构造方法,一个无参数,将x,y均设置为0,另一对坐标值为参数,设置x,y为给定坐标值.该类的show方法输出该点的坐标值.
写一个Line（线）类,该类具有两个点属性p1、p2,有参构造函数（已知直线两个顶点的坐标） ,一个计算两点间距的方法calcLength
写一个三角形类,该类具有三条边属性line1、line2、line3,有参构造函数（已知三角形三个顶点的坐标）,计算面积的方法calcArea、计算周长的方法calcPerimeter
编写一个测试Test类
第一部分完成
package aaa;
public class Point {
public double x;
public double y;
public Point(){
x=0;
y=0;
}
public Point (double x,double y){
this.x = x;
this.y = y;
}
public void show(){
System.out.println("点的坐标"+x+","+y+",");
}
第二部分完成
package aaa;
public class line {
Point p1;
Point p2;
public line(double x1,double y1,double x2,double y2){
p1 =new Point (x1,y1);
p2 =new Point (x2,y2);
}
public double CalcLength(){
return Math.sqrt((p2.x-p1.x)*(p2.x-p1.x)+(p2.y-p1.y)*(p2.y-p1.y));
}
第三部分未完成不会了
Line line1;
Line line2;
Line line3;
public Line (double x1,double y1,double x2,double y2,double x3,double y3);
line1 = new Line(x1,y1,x2,y2)
line2 = new line(x1,y1,x3,y3)
line3 = new line (x2,y2,x3,y3)

Answer 1

package aaa;
public class Triangle
{
private Line line1;
private Line line2;
private Line line3;
public Triangle(double x1,double y1,double x2,double y2,double x3,double y3){
this.line1 = new Line(x1,y1,x2,y2);
this.line2 = new Line(x1,y1,x3,y3);
this.line3 = new Line(x2,y2,x3,y3);
}
public double calcArea(){
double a = line1.CalcLength ;
double b = line2.CalcLength ;
double c = line3.CalcLength ;
return sqrt[(1/2)(a+b+c)(a+b-c)(a+c-b)(b+c-a)];
}
public double calcPerimeter(){
double a = line1.CalcLength ;
double b = line2.CalcLength ;
double c = line3.CalcLength ;
return a+b+c;
}
}
----------------------------------------------------
测试类
----------------------------------------------------
package aaa;
public class Test
{
public static void main(String[] args){
Triangle triangle = new Triangle(0,0,4,0,0,5);
System.out.println("三角形的面积为："+triangle.calcArea());
System.out.println("三角形的周长："+triangle.calcPerimeter());
}
}
如果有问题可以找我.