title: method in class cannot be applied to given types error
body: <pre><code>// CentredBall class:
    2 //   Class attribute: quantity - number of balls created
    3 //   Instance attributes: colour, radius, centre
    4 import java.awt.*;
    5 
    6 class CentredBall {
    7 
    8     /************** Data members **********************/
    9     private static int quantity = 0;
   10 
   11     private String colour;
   12     private double radius;
   13     private Point  centre;
   14     private int xCoord, yCoord;
   15 
   16     /************** Constructors **********************/
   17     //  Default constructor creates a yellow, radius 10.0 ball centred at origin (0,0)
   18     public CentredBall()    {
   19         this.colour = "yellow";
   20         this.radius = 10.0;
   21     }   
   22     
   23     public CentredBall(String colour, double radius, Point centre)  {
   24         setColour(colour);
   25         setRadius(radius);
   26         setCentre(xCoord, yCoord);
   27         quantity++;
   28     }   
   29     
   30     public CentredBall(String colour, double radius, int xCoord, int yCoord)    {
   31         setColour(colour);
   32         setRadius(radius);
   33         setxCoord(xCoord);
   34         setyCoord(yCoord);
   35         quantity++;
   36     }   
   37     
   38     /**************** Accessors ***********************/
   39     public static int getQuantity() {
   40         return quantity;
   41     }   
   42     public String getColour()   {
   43         return this.colour;
   44     }   
   45     public double getRadius()   {
   46         return this.radius;
   47     }
   48     public Point getCentre()    {
   49         return this.centre;
   50     }
   51     public int getxCoord()  {
   52         return this.xCoord;
   53     }
   54     public int getyCoord()  {
   55         return this.yCoord;
   56     }
   57 
   58     /**************** Mutators ************************/
   59     public void setColour(String colour)    {
   60         this.colour = colour;
   61     }
   62     public void setRadius(double radius)    {
   63         this.radius = radius;
   64     }
   65     public void setCentre(Point centre) {
   66         this.centre = centre;
   67     }
   68     public void setxCoord(int xCoord)   {
   69         this.xCoord = xCoord;
   70     }
   71     public void setyCoord(int yCoord)   {
   72         this.yCoord = yCoord;
   73     }
   74 
   75     /***************** Overriding methods ******************/
   76     // Overriding toString() method
   77     public String toString() {
   78         return "[" + getColour() + ", " + getRadius() + ", " + getxCoord() + ", " + getyCoord() + "]";
   79     }
   80 
   81     // Overriding equals() method
   82     public boolean equals(Object obj) {
   83         if  (obj instanceof CentredBall)    {
   84             CentredBall ball = (CentredBall) obj;
   85             return  this.getColour().equals(ball.getColour()) &amp;&amp;
   86                     this.getRadius() == ball.getRadius() &amp;&amp;
   87                     this.getxCoord() == ball.getxCoord() &amp;&amp;
   88                     this.getyCoord() == ball.getyCoord();
   89         }
   90         else
   91             return false;
   92     }
  </code></pre>
  
  <p>I keep getting this error</p>
  
  <pre><code>CentredBall.java:26: error: method setCentre in class CentredBall cannot be applied to given types;
              setCentre(xCoord, yCoord);
              ^
  required: Point
  found: int,int
  reason: actual and formal argument lists differ in length
  1 error
  </code></pre>
  
  <p>I have a few questions. pls help.</p>
  
  <ol>
  <li><p>how come the default constructor does not have a parameter for the centre at origin? I tried doing this("yellow", 10.0, (0,0)); but it doesn't work</p></li>
  <li><p>what is the use of the overriding methods? Is there any error for the <code>toString</code> and <code>equals</code> overriding methods I have created?</p></li>
  </ol>