Update the classes Triangle and Rectangle, to throw an exception if the Cartesian Point instances passed as parameter does not specify an appropriate Triangle or Rectangle. e.g. In case of Triangle, if the three points are in a straight line, or in case of Rectangle, if the lines when connected cross each other.

[ testtriangle .java ]

import graphics.*; //TO IMPORT CARTESIANPOINT CLASS
import java.io.*;
import java.lang.*;

class ClassNotMatchException extends Throwable
{
void display()
{
System.out.println("Class Not Math Exception Found");
}
}
class triangle
{
CartesianPoint p1,p2,p3;
triangle(CartesianPoint p1,CartesianPoint p2,CartesianPoint p3)
{
this.p1=p1;
this.p2=p2;
this.p3=p3;
}
public void display()
{
System.out.println("\nPOINT 1 : ( " + this.p1.getx() + " : " + this.p1.gety() + " )");
System.out.println("\nPOINT 2 : ( " + this.p2.getx() + " : " + this.p2.gety() + " )");
System.out.println("\nPOINT 3 : ( " + this.p3.getx() + " : " + this.p3.gety() + " )");
}
public void move() throws IOException
{
double newx,newy,diffx,diffy;
System.out.println("Enter New Cordinates of Point 1");

BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter x-Cordinates :");
newx=Integer.parseInt(br.readLine());
System.out.println("Enter y-Cordinates :");
newy=Integer.parseInt(br.readLine());

diffx=newx-p1.getx();
diffy=newy-p1.gety();

p1.move(newx,newy);
p2.move(p2.getx() + diffx,p2.gety() + diffy);
p3.move(p3.getx() + diffx,p3.gety() + diffy);
}
public void move(Object p1) throws IOException
{
try
{
if( !(p1 instanceof CartesianPoint))
{
ClassNotMatchException obj;
obj=new ClassNotMatchException();
throw obj;
}
else
{
double newx,newy,a,b,c;
System.out.println("Enter New Cordinates of Point 1");

BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter x-Cordinates :");
newx=Integer.parseInt(br.readLine());
System.out.println("Enter y-Cordinates :");
newy=Integer.parseInt(br.readLine());
// p1.move(newx,newy);
this.p1.move(newx,newy);
}
}
catch(ClassNotMatchException obj)
{
obj.display();
}
}
public void area()
{
double a,b,c,s,perimeter,area;

a=Math.sqrt(Math.pow((p1.getx()-p2.getx()),2)+Math.pow((p1.gety()-p2.gety()),2));
b=Math.sqrt(Math.pow((p1.getx()-p3.getx()),2)+Math.pow((p1.gety()-p3.gety()),2));
c=Math.sqrt(Math.pow((p2.getx()-p3.getx()),2)+Math.pow((p2.gety()-p3.gety()),2));
s=(a+b+c)/2;

area=Math.sqrt(s*(s-a)*(s-b)*(s-c));
System.out.println("Area of Triangle is : " + area);
}
public void perimeter()
{
double a,b,c,perimeter;

a=Math.sqrt(Math.pow((p1.getx()-p2.getx()),2)+Math.pow((p1.gety()-p2.gety()),2));
b=Math.sqrt(Math.pow((p1.getx()-p3.getx()),2)+Math.pow((p1.gety()-p3.gety()),2));
c=Math.sqrt(Math.pow((p2.getx()-p3.getx()),2)+Math.pow((p2.gety()-p3.gety()),2));

perimeter=a+b+c;
System.out.println("Perimeter of Triangle is : " + perimeter);
}
public void rotate(CartesianPoint p1,double x)
{
double newx,newy;
newx=(p1.getx() * Math.cos(x)) - (p1.gety() * Math.sin(x));
newy=(p1.getx() * Math.sin(x)) + (p1.gety() * Math.cos(x));
p1.move(newx,newy);
}
public String toString()
{
return "p1(x):"+p1.getx()+" ; p1(y):"+p1.gety()+" ; p2(x):"+p2.getx()+" ; p2(y):"+p2.gety()+" ; p3(x):"+p3.getx()+" ; p3(y):"+p3.gety();
}
public boolean equals(Object tempobj)
{
if(!(tempobj instanceof triangle))
return false;
if(this.p1.getx() != ((triangle)tempobj).p1.getx() && this.p1.gety() != ((triangle)tempobj).p1.gety())
return false;
if(this.p2.getx() != ((triangle)tempobj).p2.getx() && this.p2.gety() != ((triangle)tempobj).p2.gety())
return false;
if(this.p3.getx() != ((triangle)tempobj).p3.getx() && this.p3.gety() != ((triangle)tempobj).p3.gety())
return false;
return true;
}
}
class rectangle
{
CartesianPoint p1,p2,p3,p4;
rectangle(CartesianPoint p1,CartesianPoint p2,CartesianPoint p3,CartesianPoint p4)
{
double a,b,c,d;
this.p1=p1;
this.p2=p2;
this.p3=p3;
this.p4=p4;
a=Math.sqrt(Math.pow((p1.getx()-p2.getx()),2)+Math.pow((p1.gety()-p2.gety()),2));
b=Math.sqrt(Math.pow((p1.getx()-p4.getx()),2)+Math.pow((p1.gety()-p4.gety()),2));
c=Math.sqrt(Math.pow((p2.getx()-p3.getx()),2)+Math.pow((p2.gety()-p3.gety()),2));
d=Math.sqrt(Math.pow((p3.getx()-p4.getx()),2)+Math.pow((p3.gety()-p4.gety()),2));
if ( !((a==c && b==d) || (a==b && c==d) || (a==d && b==c) ))
{
System.out.println("IT IS NOT A RECTANGLE....");
}
}
public void display()
{
System.out.println("\nPOINT 1 : ( " + this.p1.getx() + " : " + this.p1.gety() + " )");
System.out.println("\nPOINT 2 : ( " + this.p2.getx() + " : " + this.p2.gety() + " )");
System.out.println("\nPOINT 3 : ( " + this.p3.getx() + " : " + this.p3.gety() + " )");
System.out.println("\nPOINT 4 : ( " + this.p4.getx() + " : " + this.p4.gety() + " )");
}
public void move() throws IOException
{
double newx,newy,diffx,diffy;
System.out.println("Enter New Cordinates of Point 1");

BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter x-Cordinates :");
newx=Integer.parseInt(br.readLine());
System.out.println("Enter y-Cordinates :");
newy=Integer.parseInt(br.readLine());

diffx=newx-p1.getx();
diffy=newy-p1.gety();

p1.move(newx,newy);
p2.move(p2.getx() + diffx,p2.gety() + diffy);
p3.move(p3.getx() + diffx,p3.gety() + diffy);
p4.move(p4.getx() + diffx,p4.gety() + diffy);
}
public void move(CartesianPoint p1) throws IOException
{

try
{
if( !(p1 instanceof CartesianPoint))
{
ClassNotMatchException obj;
obj=new ClassNotMatchException();
throw obj;
}
else
{
double newx,newy;
System.out.println("Enter New Cordinates of Point 1");

BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter x-Cordinates :");
newx=Integer.parseInt(br.readLine());
System.out.println("Enter y-Cordinates :");
newy=Integer.parseInt(br.readLine());
// p1.move(newx,newy);
this.p1.move(newx,newy);
}
}
catch(ClassNotMatchException obj)
{
obj.display();
}

}
public void area()
{
double a,b,c,d,s,perimeter,area=0;

a=Math.sqrt(Math.pow((p1.getx()-p2.getx()),2)+Math.pow((p1.gety()-p2.gety()),2));
b=Math.sqrt(Math.pow((p1.getx()-p4.getx()),2)+Math.pow((p1.gety()-p4.gety()),2));
c=Math.sqrt(Math.pow((p2.getx()-p3.getx()),2)+Math.pow((p2.gety()-p3.gety()),2));
d=Math.sqrt(Math.pow((p3.getx()-p4.getx()),2)+Math.pow((p3.gety()-p4.gety()),2));
if (a==c && b==d)
{
area=a*b;
}
else if( a==b && c==d)
{
area=a*c;
}
else if( a==d && b==c)
{
area=a*b;
}
System.out.println("Area of rectangle is : " + area);
}
public void perimeter()
{
double a,b,c,d,perimeter=0;
a=Math.sqrt(Math.pow((p1.getx()-p2.getx()),2)+Math.pow((p1.gety()-p2.gety()),2));
b=Math.sqrt(Math.pow((p1.getx()-p4.getx()),2)+Math.pow((p1.gety()-p4.gety()),2));
c=Math.sqrt(Math.pow((p2.getx()-p3.getx()),2)+Math.pow((p2.gety()-p3.gety()),2));
d=Math.sqrt(Math.pow((p3.getx()-p4.getx()),2)+Math.pow((p3.gety()-p4.gety()),2));
if (a==c && b==d)
{
perimeter=2*(a+b);
}
else if( a==b && c==d)
{
perimeter=2*(a+c);
}
else if( a==d && b==c)
{
perimeter=2*(a+b);
}
System.out.println("Perimeter of rectangle is : " + perimeter);
}
public void rotate(CartesianPoint p1,double x)
{
double newx,newy;
newx=(p1.getx() * Math.cos(x)) - (p1.gety() * Math.sin(x));
newy=(p1.getx() * Math.sin(x)) + (p1.gety() * Math.cos(x));
p1.move(newx,newy);
}
public String toString()
{
return "p1(x):"+p1.getx()+" ; p1(y):"+p1.gety()+" ; p2(x):"+p2.getx()+" ; p2(y):"+p2.gety()+" ; p3(x):"+p3.getx()+" ; p3(y):"+p3.gety()+" ; p4(x):"+p4.getx()+" ; p4(y):"+p4.gety();
}
public boolean equals(Object tempobj)
{
if(!(tempobj instanceof rectangle))
return false;
if(this.p1.getx() != ((rectangle)tempobj).p1.getx() && this.p1.gety() != ((rectangle)tempobj).p1.gety())
return false;
if(this.p2.getx() != ((rectangle)tempobj).p2.getx() && this.p2.gety() != ((rectangle)tempobj).p2.gety())
return false;
if(this.p3.getx() != ((rectangle)tempobj).p3.getx() && this.p3.gety() != ((rectangle)tempobj).p3.gety())
return false;
if(this.p4.getx() != ((rectangle)tempobj).p4.getx() && this.p4.gety() != ((rectangle)tempobj).p4.gety())
return false;
return true;
}
}
class testtriangle
{
public static void main(String args[]) throws IOException
{
CartesianPoint p1,p2,p3,p4;
triangle triangle_obj;
rectangle rectangle_obj;


p1=new CartesianPoint(5,5);
p2=new CartesianPoint(10,5);
p3=new CartesianPoint(10,10);
p4=new CartesianPoint(5,10);


rectangle_obj=new rectangle(p1,p2,p3,p4);
triangle_obj=new triangle(p1,p2,p3);
triangle_obj.display();
triangle_obj.perimeter();
triangle_obj.area();

triangle_obj.move(rectangle_obj);
System.out.println("After Moving of Triangle");
triangle_obj.display();
triangle_obj.perimeter();
triangle_obj.area();
/*
triangle_obj.rotate(p1,90);
triangle_obj.rotate(p2,90);
triangle_obj.rotate(p3,90);
triangle_obj.perimeter();
triangle_obj.area();

// rectangle
*/

rectangle_obj.display();
rectangle_obj.perimeter();
rectangle_obj.area();

/*triangle_obj.move();
System.out.println("After Moving of rectangle");
rectangle_obj.display();
rectangle_obj.perimeter();
rectangle_obj.area();*/

rectangle_obj.rotate(p1,90);
rectangle_obj.rotate(p2,90);
rectangle_obj.rotate(p3,90);
rectangle_obj.perimeter();
rectangle_obj.area();

System.out.println("hasCode of triangle :"+ triangle_obj.hashCode());
System.out.println("hasCode of rectangle :"+ rectangle_obj.hashCode());
if(triangle_obj.equals(rectangle_obj))
System.out.println("BOTH OBJECTS ARE EQUAL");
else
System.out.println("BOTH OBJECTS ARE NOT EQUAL");
}
}

[ graphics.java ] 
(save it in graphics folder)

package graphics;
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);
}
}