Make the class Cartesian Point, belong to a package called edu. gtu. geometry, the classes Polygon, Triangle and Rectangle belong to the package edu. gtu. geometry. shapes and the classes Test Cartesian Point, Test Triangle, Test Rectangle and Test Polygon belong to the package edu. gtu. test. Use appropriate access specifiers for the classes and the members of the classes defined in the earlier exercises. Now onwards all the classes must be defined in a package.

[ polygon.java ] 

(save it in edu/gtu/geometry/shapes folder)

package edu.gtu.geometry.shapes;
import edu.gtu.geometry.*;
import java.io.*;
abstract class polygon
{
CartesianPoint cp[];
polygon()
{
}
polygon(CartesianPoint p[])
{
cp=new CartesianPoint[p.length];

for(int i=0;i<p.length;i++)
{
cp[i]=p[i];
}
System.out.println(cp.length);
}
double perimeter()
{
double peri=0,a[];
a=new double[cp.length];

for(int i=0;i<cp.length;i++)
{
if( (i+1) < cp.length)
a[i]=Math.sqrt(Math.pow((cp[i].getx()-cp[i+1].getx()),2)+Math.pow((cp[i].gety()-cp[i+1].gety()),2));
else
a[i]=Math.sqrt(Math.pow((cp[i].getx()-cp[0].getx()),2)+Math.pow((cp[i].gety()-cp[0].gety()),2));
peri=peri+a[i];
}
return peri;
}
abstract void area();
public void move(double x,double y)
{
cp[0].move(x,y);
}
public void move(CartesianPoint p) throws IOException
{
for(int i=0;i<cp.length;i++)
{
if(cp[i].getx()==p.getx() && cp[i].gety()==p.gety())
{
double tempx,tempy;
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter Value of x : ");
tempx=Double.parseDouble(br.readLine());
System.out.println("Enter Value of y : ");
tempy=Double.parseDouble(br.readLine());
cp[i].move(tempx,tempy);
p.move(tempx,tempy);
}
}
}
}

[ rectangle.java ]

(save it in edu/gtu/geometry/shapes folder)

package edu.gtu.geometry.shapes;

import edu.gtu.geometry.shapes.*;

import edu.gtu.geometry.*;

import java.io.*;

public class rectangle extends polygon

{

public rectangle(CartesianPoint p[])

{

super(p);

}

public void area()

{

double s=0,area,temp=0,a[];

a=new double[cp.length];

for(int i=0;i<cp.length;i++)

{

if( (i+1) < cp.length)

a[i]=Math.sqrt(Math.pow((cp[i].getx()-cp[i+1].getx()),2)+Math.pow((cp[i].gety()-cp[i+1].gety()),2));

else

a[i]=Math.sqrt(Math.pow((cp[i].getx()-cp[0].getx()),2)+Math.pow((cp[i].gety()-cp[0].gety()),2));

}

area=a[0]*a[1];

System.out.println("AREA OF TRIANGLE IS : "+area);

}

public void display()

{

for(int i=0;i<cp.length;i++)

{

System.out.println("POINT 1 : ("+cp[i].getx() + ":" + cp[i].gety() + ")");

}

}

}

[ triangle.java ]

(save it in edu/gtu/geometry/shapes folder)

package edu.gtu.geometry.shapes;

import edu.gtu.geometry.shapes.*;

import edu.gtu.geometry.*;

import java.io.*;

public class triangle extends polygon

{

public triangle(CartesianPoint p[])

{

super(p);

}

public void area()

{

double s=0,area,temp=0,a[];

a=new double[cp.length];

for(int i=0;i<cp.length;i++)

{

if( (i+1) < cp.length)

a[i]=Math.sqrt(Math.pow((cp[i].getx()-cp[i+1].getx()),2)+Math.pow((cp[i].gety()-cp[i+1].gety()),2));

else

a[i]=Math.sqrt(Math.pow((cp[i].getx()-cp[0].getx()),2)+Math.pow((cp[i].gety()-cp[0].gety()),2));

}

s=super.perimeter()/2;

temp=s;

for(int i=0;i<cp.length;i++)

{

temp=temp*(s-a[i]);

}

area=Math.sqrt(temp);

System.out.println("AREA OF TRIANGLE IS : "+area);

}

public double perimeter()

{

return super.perimeter();

}

public void display()

{

for(int i=0;i<cp.length;i++)

{

System.out.println("POINT 1 : ("+cp[i].getx() + ":" + cp[i].gety() + ")");

}

}

}

[ CartesianPoint.java ]

(save it in edu/gtu/geometry folder)

package edu.gtu.geometry;

public class CartesianPoint

{

double x,y;

public CartesianPoint()

{

}

public CartesianPoint(double x)

{

System.out.println("CONSTRUCTOR WTIH ONE PARAMETER");

this.x=x;

this.y=x;

}

public CartesianPoint(double x,double y)

{

System.out.println("CONSTRUCTOR WTIH TWO PARAMETER");

this.x=x;

this.y=y;

}

public double getx()

{

return x;

}

public double gety()

{

return y;

}

public void move(double x,double y)

{

System.out.println("MOVE METHOD WTIH ONE PARAMETER");

this.x=x;

this.y=y;

}

public void move(double x)

{

System.out.println("MOVE METHOD WTIH TWO PARAMETER");

this.x=x;

this.y=x;

}

public void display()

{

System.out.println("Value of x : " + x);

System.out.println("Value of y : " + y);

}

}

[ testrectangle.java ]

(save it in edu/gtu/test folder)

package edu.gtu.test;

import edu.gtu.geometry.*;

import edu.gtu.geometry.shapes.*;

import java.io.*;

class testrectangle

{

public static void main(String args[])  throws IOException

{

CartesianPoint p[];

p=new CartesianPoint[3];

p[0]=new CartesianPoint(5,5);

p[1]=new CartesianPoint(10,5);

p[2]=new CartesianPoint(10,10);

rectangle obj;

obj=new rectangle(p);

System.out.println("PERIMETER OF RECTANGLE IS:" + obj.perimeter());

obj.area();

obj.display();

obj.move(50,50);

obj.area();

obj.area();

obj.display();

obj.move(p[1]);

obj.area();

obj.area();

obj.display();

}

}

[ testtriangle.java ]

(save it in edu/gtu/test folder)

package edu.gtu.test;

import edu.gtu.geometry.*;

import edu.gtu.geometry.shapes.*;

import java.io.*;

class testtriangle

{

public static void main(String args[])  throws IOException

{

CartesianPoint p[];

p=new CartesianPoint[3];

p[0]=new CartesianPoint(5,5);

p[1]=new CartesianPoint(10,5);

p[2]=new CartesianPoint(10,10);

triangle obj;

obj=new triangle(p);

System.out.println("PERIMETER OF TRIANGLE IS:" + obj.perimeter());

obj.area();

obj.display();

obj.move(50,50);

obj.area();

obj.area();

obj.display();

obj.move(p[2]);

obj.area();

obj.area();

obj.display();

}

}