我目前有一个包含所有计算的Triangle类。
public class Triangle
{
private double x1;
private double y1;
private double x2;
private double y2;
private double x3;
private double y3;
private double lengthA;
private double lengthB;
private double lengthC;
private double angleA;
private double angleB;
private double angleC;
private double perimeter;
private double height;
private double area;
public double calcArea()
{
area = .5 * lengthC * height;
return area;
}
public double calcPerimeter()
{
perimeter = lengthA + lengthB + lengthC;
return perimeter;
}
public double lengthA()
{
lengthA = Math.sqrt(Math.pow((x2 - x3),2) + Math.pow(height,2));
return lengthA;
}
public double lengthB()
{
lengthB = Math.sqrt(Math.pow((x3 - x1),2) + Math.pow(height,2));
return lengthB;
}
public double lengthC()
{
lengthC = x2 - x1;
return lengthC;
}
public double getHeight()
{
height = y3 - y1;
return height;
}
public double angleA()
{
angleA = Math.abs(Math.toDegrees(Math.asin(height / lengthB)));
return angleA;
}
public double angleB()
{
angleB = Math.abs(Math.toDegrees(Math.asin(height / lengthA)));
return angleB;
}
public double angleC()
{
angleC = 180 - angleA - angleB;
return angleC;
}
}
我还有一个TriangleTester类，它使用JOptionPane来获取三角形的坐标。
import javax.swing.*;
public class TriangleTester
{
public static void main (String [] args)
{
double x1;
double y1;
double x2;
double y2;
double x3;
double y3;
String v1;
String v2;
String v3;
String v4;
String v5;
String v6;
v1 = JOptionPane.showInputDialog("Enter x1 for point A");
v2 = JOptionPane.showInputDialog("Enter y1 for point A");
v3 = JOptionPane.showInputDialog("Enter x2 for point B");
v4 = JOptionPane.showInputDialog("Enter y2 for point B");
v5 = JOptionPane.showInputDialog("Enter x3 for point C");
v6 = JOptionPane.showInputDialog("Enter y3 for point C");
x1 = Integer.parseInt(v1);
y1 = Integer.parseInt(v2);
x2 = Integer.parseInt(v3);
y2 = Integer.parseInt(v4);
x3 = Integer.parseInt(v5);
y3 = Integer.parseInt(v6);
Triangle tri = new Triangle();
double lengthA = tri.lengthA();
double lengthB = tri.lengthB();
double lengthC = tri.lengthC();
double angleA = tri.angleA();
double angleB = tri.angleB();
double angleC = tri.angleC();
double perimeter = tri.calcPerimeter();
double height = tri.getHeight();
double area = tri.calcArea();
System.out.printf("Set up triangle with coordinates (" + x1 + "," + y1 + "), (" + x2 + "," + y2 + "), (" + x3 + "," + y3 + ")");
System.out.printf("\nArea:\t\t\t\t" + area);
System.out.printf("\nPerimeter:\t\t" + perimeter);
System.out.printf("\nLength side a:\t" + lengthA);
System.out.printf("\nLength side b:\t" + lengthB);
System.out.printf("\nLength side c:\t" + lengthC);
System.out.printf("\nHeight h:\t\t" + height);
System.out.printf("\nAngle A:\t\t\t" + angleA);
System.out.printf("\nAngle B:\t\t\t" + angleB);
System.out.printf("\nAngle C:\t\t\t" + angleC);
}
}
当我运行测试器代码时，它会打印带有正确x和y值的坐标，但是其他所有内容最终打印为0.我相信这是因为我没有在x和y值之间建立任何关联Triangle类和TriangleTester类。如何让Triangle类使用TriangleTester类中输入的x和y值来计算答案？感谢。
答案 0 :(得分：0)
这里的主要想法是你使用吸气剂作为制定者。 您没有在类之间传递setter方法的数据 主程序
package triangles;
import javax.swing.*;
public class Triangles {
/**
* @param args the command line arguments
*/
public static void main(String[] args)
{
double x1;
double y1;
double x2;
double y2;
double x3;
double y3;
String v1;
String v2;
String v3;
String v4;
String v5;
String v6;
v1 = JOptionPane.showInputDialog("Enter x1 for point A");
v2 = JOptionPane.showInputDialog("Enter y1 for point A");
v3 = JOptionPane.showInputDialog("Enter x2 for point B");
v4 = JOptionPane.showInputDialog("Enter y2 for point B");
v5 = JOptionPane.showInputDialog("Enter x3 for point C");
v6 = JOptionPane.showInputDialog("Enter y3 for point C");
x1 = Integer.parseInt(v1);
y1 = Integer.parseInt(v2);
x2 = Integer.parseInt(v3);
y2 = Integer.parseInt(v4);
x3 = Integer.parseInt(v5);
y3 = Integer.parseInt(v6);
Triangle tri = new Triangle();
//set all needed data
tri.setLengthA(x2,x3);
tri.setLengthB(x3,x1);
tri.setLengthC(x2,x1);
tri.setHeight(y3,y1);
// set calculations off the data
tri.setAngleA();
tri.setAngleB();
tri.setAngleC();
double perimeter = tri.calcPerimeter();
double area = tri.calcArea();
System.out.printf("Set up triangle with coordinates (" + x1 + "," + y1 + "), (" + x2 + "," + y2 + "), (" + x3 + "," + y3 + ")");
System.out.printf("\nArea:\t\t\t\t" + area);
System.out.printf("\nPerimeter:\t\t" + perimeter);
System.out.printf("\nLength side a:\t" + tri.lengthA);
System.out.printf("\nLength side b:\t" + tri.lengthB);
System.out.printf("\nLength side c:\t" + tri.lengthC);
System.out.printf("\nHeight h:\t\t" + tri.height);
System.out.printf("\nAngle A:\t\t\t" + tri.angleA);
System.out.printf("\nAngle B:\t\t\t" + tri.angleB);
System.out.printf("\nAngle C:\t\t\t" + tri.angleC);
}
}
和你的班级
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package triangles;
/**
*
* @author jstil
*/
public class Triangle {
private double x1;
private double y1;
private double x2;
private double y2;
private double x3;
private double y3;
public double lengthA;
public double lengthB;
public double lengthC;
public double angleA;
public double angleB;
public double angleC;
private double perimeter;
public double height;
private double area;
public double calcArea()
{
area = .5 * lengthC * height;
return area;
}
public double calcPerimeter()
{
perimeter = lengthA + lengthB + lengthC;
return perimeter;
}
public void setLengthA( double x2 , double x3)
{
lengthA = Math.sqrt(Math.pow((x2 - x3),2) + Math.pow(height,2));
}
public void setLengthB(double x3, double x1)
{
lengthB = Math.sqrt(Math.pow((x3 - x1),2) + Math.pow(height,2));
}
public void setLengthC(double x2, double x1)
{
lengthC = x2 - x1;
}
public void setHeight(double y3, double y1)
{
height = y3 - y1;
}
public void setAngleA()
{
angleA = Math.abs(Math.toDegrees(Math.asin(height/ lengthB)));
}
public void setAngleB()
{
angleB = Math.abs(Math.toDegrees(Math.asin(height / lengthA)));
}
public void setAngleC()
{
angleC = 180 - angleA - angleB;
}
}