title: java circle inside a circle , how to know if two circles overlap
body: <p>this is some code i wrote in java, it is a circle object class. i wrote methods i need two more methods and im struggeling with the first one is 
  a method that contains (circle c) that returns true if the specified circle c is inside circle. and the second one is a method overlaps(circle c) that returns true if th especified circle c overlaps with this circle. all i need is how to make those two methods with the parameter being another circle object</p>
  
  <p>this is my code</p>
  
  <pre><code>public class Circle
  {
  // instance variables - replace the example below with your own
  private double radius;
  private double centerX;
  private double centerY;
  
  /**
   * Constructor for objects of class Circle
   */
  public Circle()
  {
    this.radius = 1;
    this.centerX = 0;
    this.centerY = 0;
  }
  /**
   * Constructor for objects of class Circle
   */
  public Circle(double radius, double centerx, double centery)
  {
    this.radius = radius;
    this.centerX = centerX;
    this.centerY = centerY;
  }
   /**
   * Constructor for objects of class Circle
   */
  public Circle(double pRadius)
  {
       radius = pRadius;
  }
  /**
   * An example of a method - replace this comment with your own
   * 
   * @param  y   a sample parameter for a method
   * @return     the sum of x and y 
   */
  public void setRadius(double pRadius)
  {
      radius = pRadius;
  }
  /**
   * getRadius method will return the radius of the cricle
   * @param none 
   * @return radius of type double
   */
   public double getRadius()
  {
      return radius ;
  }
  /**
   * getcenterX method will return the x coordinates of the circle
   * @param none 
   * @return centerx of type double
   */
   public double getCenterX()
  {
      return centerX ;
  }
  /**
   * getcenterY method will return the y coordinates of the circle
   * @param none 
   * @return centery of type double
   */
   public double getCenterY()
  {
      return centerY ;
  }
  /**
   * 
   */
     public double calcPerimeter()
  {
      return 2*Math.PI*getRadius();
  }
  /**
   * 
   */
     public double calcArea()
  {
      return Math.PI*Math.pow(getRadius(),2);
  }
  /**
   * 
   */
  public double distance(double x1, double y1, double x2, double y2)
  {
      return ( Math.sqrt(Math.pow(x1-x2,2)+ Math.pow(y1-y2,2))) ;
  
  }
  /**
   * 
   */
  public boolean contains(double x, double y)
  {
      double dist = distance(x, y, centerX, centerY); // calculate the distance between the point(x,y) and center of the circle
      boolean flag = false;
      if ( dist &lt; radius)
      {
          flag = true;
  
      }
      else if ( dist &gt; radius)
      {
         flag = false ;
      }
      else 
      {
          System.out.println("The point is on the circle.");
      }
      return flag;
  }
  
  }
  /**
   * 
   */
  public String toString()
  {
      String outString = "The radius of the circle is: " + getRadius() + "\nThe perimeter of the circle object is; " + calcPerimeter()+ "\nThe area of the circle is: " + calcArea() ;
      return outString;
  }
  </code></pre>
  
  <p>}</p>