I am having problem with the following code
public void grow(int size), can't seem to get it working
import ou.*;
import java.util.*;
/**
* Class DiscoLight
* This class uses the Circle class, and the Shapes window
* to simulate a disco light, that grows and shrinks and
* changes colour.
*
* @author M255 CT
* @version 1.0
*/
public class DiscoLight
{
/* instance variables */
private Circle light; // simulates a circular disco light in the Shapes window
private Random randomNumberGenerator;
/**
* Default constructor for objects of class DiscoLight
*/
public DiscoLight()
{
super();
this.randomNumberGenerator = new Random();
}
/**
* Returns a randomly generated int between 0 (inclusive)
* and number (exclusive). For example if number is 6,
* the method will return one of 0, 1, 2, 3, 4, or 5.
*/
public int getRandomInt(int number)
{
return this.randomNumberGenerator.nextInt(number);
}
/**
* student to write code and comment here for setLight(Circle) for Q4(i)
*/
public void setLight(Circle aCircle)
{
this.light = aCircle;
}
/**
* student to write code and comment here for getLight() for Q4(i)
*/
public Circle getLight()
{
return this.light;
}
/**
* Sets the argument to have a diameter of 50, an xPos
* of 122, a yPos of 162 and the colour GREEN.
* The method then sets the receiver's instance variable
* light, to the argument aCircle.
*/
public void addLight(Circle aCircle)
{
//Student to write code here, Q4(ii)
this.light = aCircle;
this.light.setDiameter(50);
this.light.setXPos(122);
this.light.setYPos(162);
this.light.setColour(OUColour.GREEN);
}
/**
* Randomly sets the colour of the instance variable
* light to red, green, or purple.
*/
public void changeColour()
{
int i = getRandomInt(3);
if (i == 0)
{
this.light.setColour(OUColour.RED);
}
else if (i == 1)
{
this.light.setColour(OUColour.GREEN);
}
else
{
this.light.setColour(OUColour.PURPLE);
}
}
/**
* Grows the diameter of the circle referenced by the
* receiver's instance variable light, to the argument size.
* The diameter is incremented in steps of 2,
* the xPos and yPos are decremented in steps of 1 until the
* diameter reaches the value given by size.
* Between each step there is a random colour change. The message
* delay(anInt) is used to slow down the graphical interface, as required.
*/
public void grow(int size)
{
for (int i = 0; i < size; i++)
{
this.aDiameter[i] = aDiameter + 2;
this.xPos[i] = xPos - 1;
this.yPos[i] = yPos - 1;
}
}
/**
* Shrinks the diameter of the circle referenced by the
* receiver's instance variable light, to the argument size.
* The diameter is decremented in steps of 2,
* the xPos and yPos are incremented in steps of 1 until the
* diameter reaches the value given by size.
* Between each step there is a random colour change. The message
* delay(anInt) is used to slow down the graphical interface, as required.
*/
public void shrink(int size)
{
//student to write code here, Q4(v)
}
/**
* Expands the diameter of the light by the amount given by
* sizeIncrease (changing colour as it grows).
*
* The method then contracts the light until it reaches its
* original size (changing colour as it shrinks).
*/
public void lightCycle(int sizeIncrease)
{
//student to write code here, Q4(vi)
}
/**
* Prompts the user for number of growing and shrinking
* cycles. Then prompts the user for the number of units
* by which to increase the diameter of light.
* Method then performs the requested growing and
* shrinking cycles.
*/
public void runLight()
{
//student to write code here, Q4(vii)
}
/**
* Causes execution to pause by time number of milliseconds
*/
private void delay(int time)
{
try
{
Thread.sleep(time);
}
catch (Exception e)
{
System.out.println(e);
}
}
}