$//$ This file contains material supporting section $2\mathrm{.}9$ of the textbook:$//$ "Object Oriented Software Engineering" and is issued under the open$-$source$//$ license found at www$.$lloseng.com $/***$ This class contains instances of coordinates in either polar or $*$ cartesian format. It also provides the utilities to convert $*$ them into the other type. It is not an optimal design, it is used $*$ only to illustrate some design issues. $**$ @author Fran$$ois B$$langer $*$ @author Dr Timothy C$.$ Lethbridge $*$ @version July $2000*/$public class PointCP$\{//$Instance variables $************************************************/***$ Contains C$($artesian$)$ or P$($olar$)$ to identify the type of $*$ coordinates that are being dealt with. $*/$ private char typeCoord; $/***$ Contains the current value of X or RHO depending on the type $*$ of coordinates. $*/$ private double xOrRho; $/***$ Contains the current value of Y or THETA value depending on the $*$ type of coordinates. $*/$ private double yOrTheta; $//$Constructors $******************************************************/***$ Constructs a coordinate object, with a type identifier. $*/$ public PointCP$($char type, double xOrRho, double yOrTheta$)\{$ if$($type $!=\text{'}$C$\text{'}$ && type $!=\text{'}$P$\text{'})$ throw new IllegalArgumentException$()$; this.xOrRho $=$ xOrRho; this.yOrTheta $=$ yOrTheta; typeCoord $=$ type; $\}//$Instance methods $**************************************************$ public double getX$()\{$ if$($typeCoord $==\text{'}$C$\text{'})$ return xOrRho; else return $($Math$.$cos$($Math$.$toRadians$($yOrTheta$))*$ xOrRho$)$; $\}$ public double getY$()\{$ if$($typeCoord $==\text{'}$C$\text{'})$ return yOrTheta; else return $($Math$.$sin$($Math$.$toRadians$($yOrTheta$))*$ xOrRho$)$; $\}$ public double getRho$()\{$ if$($typeCoord $==\text{'}$P$\text{'})$ return xOrRho; else return $($Math$.$sqrt$($Math$.$pow$($xOrRho$,2)+$ Math.pow$($yOrTheta$,2)))$; $\}$ public double getTheta$()\{$ if$($typeCoord $==\text{'}$P$\text{'})$ return yOrTheta; else return Math.toDegrees$($Math$.$atan$2($yOrTheta$,$ xOrRho$))$; $\}/***$ Converts Cartesian coordinates to Polar coordinates. $*/$ public void convertStorageToPolar$()\{$ if$($typeCoord $!=\text{'}$P$\text{'})\{//$Calculate RHO and THETA double temp $=$ getRho$()$; yOrTheta $=$ getTheta$()$; xOrRho $=$ temp; typeCoord $=\text{'}$P$\text{'}$; $//$Change coord type identifier $\}\}/***$ Converts Polar coordinates to Cartesian coordinates. $*/$ public void convertStorageToCartesian$()\{$ if$($typeCoord $!=\text{'}$C$\text{'})\{//$Calculate X and Y double temp $=$ getX$()$; yOrTheta $=$ getY$()$; xOrRho $=$ temp; typeCoord $=\text{'}$C$\text{'}$;$//$Change coord type identifier $\}\}/***$ Calculates the distance in between two points using the Pythagorean $*$ theorem $($C $^2=$ A $^2+$ B $^2).$ Not needed until E$2\mathrm{.}30.**$ @param pointA The first point. $*$ @param pointB The second point. $*$ @return The distance between the two points. $*/$ public double getDistance$($PointCP pointB$)\{//$ Obtain differences in X and Y$,$ sign is not important as these values $//$ will be squared later. double deltaX $=$ getX$()-$ pointB.getX$()$; double deltaY $=$ getY$()-$ pointB.getY$()$; return Math.sqrt$(($Math$.$pow$($deltaX$,2)+$ Math.pow$($deltaY$,2)))$; $\}/***$ Rotates the specified point by the specified number of degrees. $*$ Not required until E$2\mathrm{.}30**$ @param point The point to rotate $*$ @param rotation The number of degrees to rotate the point. $*$ @return The rotated image of the original point. $*/$ public PointCP rotatePoint$($double rotation$)\{$ double radRotation $=$ Math.toRadians$($rotation$)$; double X $=$ getX$()$; double Y $=$ getY$()$; return new PointCP$(\text{'}$C$\text{'},($Math$.$cos$($radRotation$)*$ X$)-($Math$.$sin$($radRotation$)*$ Y$),($Math$.$sin$($radRotation$)*$ X$)+($Math$.$cos$($radRotation$)*$ Y$))$; $\}/***$ Returns information about the coordinates. $**$ @return A String containing information about the coordinates. $*/$ public String toString$()\{$ return "Stored as $"+($typeCoord $==\text{'}$C$\text{'}?$ "Cartesian $("+$ getX$()+","+$ getY$()+")"$ : "Polar $["+$ getRho$()+","+$ getTheta$()+"]")+"$

$"$; $\}\}$ This is the file you'll file PointCP.java