Maintain one to one mapping between objects
- by Rohan West
Hi there, i have the following two classes that provide a one to one mapping between each other. How do i handle null values, when i run the second test i get a stackoverflow exception. How can i stop this recursive cycle? Thanks
[TestMethod]
public void SetY()
{
var x = new X();
var y = new Y();
x.Y = y;
Assert.AreSame(x.Y, y);
Assert.AreSame(y.X, x);
}
[TestMethod]
public void SetYToNull()
{
var x = new X();
var y = new Y();
x.Y = y;
y.X = null;
Assert.IsNull(x.Y);
Assert.IsNull(y.X);
}
public class X
{
private Y _y;
public Y Y
{
get { return _y; }
set
{
if(_y != value)
{
if(_y != null)
{
_y.X = null;
}
_y = value;
if(_y != null)
{
_y.X = this;
}
}
}
}
}
public class Y
{
private X _x;
public X X
{
get { return _x; }
set
{
if (_x != value)
{
if (_x != null)
{
_x.Y = null;
}
_x = value;
if (_x != null)
{
_x.Y = this;
}
}
}
}
}
