File $1$:

$/**$

This class represents points in the plane.

$*/$

public class Point

$\{$

private double x;

private double y;

public Point$()//$ default constructor

$\{$

this.x $=0\mathrm{.}0$;

this.y $=0\mathrm{.}0$;

$\}$

$/**$

Create a Point object with the given coordinates.

@param x x$-$coordinate value for the new Point object

@param y y$-$coordinate value for the new Point object

$*/$

public Point$($double x$,$ double y$)$

$\{$

$//$ implementation

$\}$

$/**$

Change this Point object to have the given x$-$coordinate.

@param newX new x$-$coordinate for this Point object

$*/$

public void setX$($double newX$)$

$\{$

$//$ implementation

$\}$

$/**$

Get the x coordinate of this Point object.

@return this Point's x$-$coordinate

$*/$

public double getX$()$

$\{$

$//$ implementation

$\}$

$/**$

Change this Point object to have the given y$-$coordinate.

@param newY new y$-$coordinate for this Point object

$*/$

public void setY$($double newY$)$

$\{$

$//$ implementation

$\}$

$/**$

Get the y$-$coordinate of this Point object.

@return this Point's y$-$coordinate

$*/$

public double getY$()$

$\{$

$//$ implementation

$\}$

$/**$

Determine if this Point object has the same x$-$coordinate

and the same y$-$coordinate as the given Point.

@param p a reference to a second Point object

@return true if the given Point is equal to this Point

$*/$

public boolean equals$($Point p$)$

$\{$

$//$ implementation

$\}$

$/**$

Determine which quadrant of the plane this Point is in$.$

Quadrant $1$ has positive x and y coordinates.

Quadrant $2$ has negative x coordinates and positice y coordinates.

Quadrant $3$ has negative x and y coordinates.

Quadrant $4$ has positive x coordinates and negative y coordinates.

Note: The positive x and y axes are in quadranr $1.$

The negative x axis is in quarant $2.$

The negative y axis is in quadrant $3.$

@return the quadrant number of this Point object

$*/$

public int quadrant$()$

$\{$

$//$ implementation

$\}$

public String toString$()$

$\{$

return "Point: $["+$ x $+","+$ y $+"]"$;

$\}$

$\}$

File $2$:

$/**$

This class represents circles in the plane.

$*/$

public public class Circle

$\{$

private double radius;

private Point center;

public Circle$()//$ default constructor

$\{$

this.radius $=0$;

this.center $=$ new Point$(0,0)$;

$\}$

public Circle$($double r$)$

$\{$

this.radius $=$ r;

this.center $=$ new Point$(0,0)$;

$\}$

$/**$

Create a Circle object with the given radius and center Point.

@param r radius for the new Circle object

@param c center Point for the new Circle object

$*/$

public Circle$($double r$,$ Point c$)$

$\{$

$//$ implementation

$\}$

$/**$

Change this Circle's center point to be the given point.

@param center new center Point for the this Circle object

$*/$

public void setCenter$($Point center$)$

$\{$

$//$ implementation

$\}$

public Point getCenter$()$

$\{$

return this.center;

$\}$

public void setRadius$($double r$)$

$\{$

this.radius $=$ r;

$\}$

public double getRadius$()$

$\{$

return this.radius;

$\}$

$/**$

Translate the center of this circle by the given

amounts in the x and y directions.

@param dx how much to move the center of this Circle in the x$-$direction

@param dy how much to move the center of this Circle in the y$-$direction

$*/$

public void translateBy$($double dx$,$ double dy$)$

$\{$

$//$ implementation

$\}$

$/**$

Translate the center of this circle to the given

amounts in the x and y directions.

@param x new x$-$coordinate for the center of this Circle

@param y new y$-$coordinate for the center of this Circle

$*/$

public void translateTo$($double x$,$ double y$)$

$\{$

$//$ implementation

$\}$

public String toString$()$

$\{$

return "Circle: r $="+$ radius $+",$ center $=["+$ center.getX$()+","+$ center.getY$()+"]"$;

$\}$

$\}$

File $3($Read$-$Only$)$

import java.util.Scanner;

public class Tester

$\{$

public static void main$($String$[]$ args$)$

$\{$

Scanner in $=$ new Scanner$($System$.$in$)$;

int testCase $=$ in$.$nextInt$()$;

if $(1==$ testCase$)$

$\{$

Point p$1=$ new Point$()$;

p$1.$setX$(4)$;

p$1.$setY$(-4)$;

System.out.println$($ p$1)$;

Point p$2=$ new Point$()$;

p$2.$setX$(-4)$;

p$2.$setY$(4)$;

System.out.println$($ p$2)$;

System.out.println$($ p$1.$quadrant$())$;

System.out.println$($ p$2.$quadrant$())$;

System.out.println$($ p$1.$equals$($p$2))$;

$\}$

else if $(2==$ testCase$)$

$\{$

Circle c $=$ new Circle$()$;

Point p $=$ new Point$()$;

p$.$setX$(4)$;

p$.$setY$(5)$;

c$.$setRadius$(10)$;

c$.$setCenter$($p$)$;

System.out.println$($ c $)$;

c$.$translateBy$(2,-2)$;