private AVLNode removeMax()
{
if (getRightSubTree() == null)
{
return(removeSelf());
}
setRight(right.removeMax(), right.right);
if (relativePosition < 0)
{
relativePosition++;
}
recalcHeight();
return(balance());
}
/**
* Removes this node from the tree.
*
* @return the node that replaces this one in the parent
*/
private AVLNode removeSelf()
{
if (getRightSubTree() == null && getLeftSubTree() == null)
{
return(null);
}
if (getRightSubTree() == null)
{
if (relativePosition > 0)
{
left.relativePosition += relativePosition + (relativePosition > 0 ? 0 : 1);
}
left.max().setRight(null, right);
return(left);
}
if (getLeftSubTree() == null)
{
right.relativePosition += relativePosition - (relativePosition < 0 ? 0 : 1);
right.min().setLeft(null, left);
return(right);
}
if (heightRightMinusLeft() > 0)
{
// more on the right, so delete from the right
AVLNode rightMin = right.min();
value = rightMin.value;
if (leftIsPrevious)
{
left = rightMin.left;
}
right = right.removeMin();
if (relativePosition < 0)
{
relativePosition++;
}
}
else
{
// more on the left or equal, so delete from the left
AVLNode leftMax = left.max();
value = leftMax.value;
if (rightIsNext)
{
right = leftMax.right;
}
AVLNode leftPrevious = left.left;
left = left.removeMax();
if (left == null)
{
// special case where left that was deleted was a double link
// only occurs when height difference is equal
left = leftPrevious;
leftIsPrevious = true;
}
if (relativePosition > 0)
{
relativePosition--;
}
}
recalcHeight();
return(this);
}