## Description

This problem will give you an opportunity to create class representing a point in 2D Cartesian space in both C++ and Java. This will enable you to become familiar with the two languages and explore the similarities and differences in the languages.

Begin by implementing the C++ version after lecture 2, then create the Java implementation after lecture 3.

Important note: There are a number of implementations of a 2D point available on the web in both C++ and Java. By doing this exercise yourself, without consulting them, you will gain valuable experience implementng classes in C++ and Java that you will not gain by simply copying someone else’s code.

## Java Version

Define a Java class Point2D in the package “edu.northeastern.cs_5004” The class represents a point in 3D Cartesian space. Define the following private fields:

Field name Type Description

final x float the X coordinate of the point

final y float the Y coordinate of the point

Define the following public methods:

Method name Type Parameters Description

Point2D none none Constructor initializes this.x and this.y to 0.0

Point2D none

float x

float y

Constructor initializes instance this.x and this.y to x, and y

Point2D none

Point2D point

Constructor intializes x and y to x and y of point (copy constructor)

getX float none Returns the x coordinate of the point

getY float none Returns the y coordinate of the point

getDistance float

Point2D point

Returns the distance between a point and this point

plus Point2D

Point2D

Returns Point2D representing sum of this point and another point†. The sum of two points is another point whose x and y values are the sum of the two point x and y values.

minus Point2D

Point2D point

Returns Point2D representing difference of this point and another point The difference of two points is another point whose x and y values are the difference of the two point x and y values.

minus Point2D none Returns Point2D representing a point with then negative of this point’s coordinates

equals bool

Object obj

Returns true if ‘obj’ is a Point2D that is equal to this point. Note that direct comparison of floats does not work correctly for float values of infinity and NaN (not-a-number). Try boxing x and y values as Float and calling equals() for each with other x and y values.

hashCode int none Returns int hash code for this point. Required when implementing equals(). A simple implemementation calls the utility function Objects.hash(f1,f2).

† For more on this operation, see Addition of Coordinates.

Define the class and implement its methods in “Point2D.java” in the subdirectory “edu/northeastern/cs_5004′. Create a JUnit test class with a main program in the file in “Point2D_main.java” that exercises the functionality of the Point2D class by creating points using both constructors, measuring their distances, and testing points for equality..

The class, fields, and function definitions, and test functions should have complete “Javadoc” style documentation. This follows the same style as we used with DOxygen for C and C++.