/// <summary>
/// Returns the node containing the data specified
/// </summary>
/// <param name="data">The data to look for in the linked list</param>
/// <returns>The node that contains the data</returns>
private Node <T> Find(T data)
{
Node <T> current = head;
T currentData;
bool firstIteration = true;
// While data is not equal to current data loop
do
{
// Determine if first iteration, if it is make first iteration false and after update current
if (firstIteration)
{
firstIteration = false;
}
else
{
current = current.GetNext();
}
// Determine if current is null
if (current == null)
{
return(null);
}
else
{
currentData = current.GetData();
}
} while (currentData.CompareTo(data) < 0 || currentData.CompareTo(data) > 0);
return(current);
}
public void TestGetData()
{
Employee emp1 = new Employee(1);
Node <Employee> node1 = new Node <Employee>(emp1);
Assert.That(node1.GetData(), Is.EqualTo(emp1));
}
/// <summary>
/// Change the supplied node's data to the data value passed
/// </summary>
/// <param name="newData">The new data to set</param>
/// <param name="node">The node to have its data replaced</param>
/// <returns>The old data from the node</returns>
private T SetData(T newData, Node <T> node)
{
T oldData = node.GetData();
node.SetData(newData);
return(oldData);
}
public void TestDataArgContructor()
{
Employee emp1 = new Employee(1);
Node <Employee> node1 = new Node <Employee>(emp1);
Assert.That(node1, Is.Not.Null);
Assert.That(node1.GetData(), Is.EqualTo(emp1));
Assert.That(node1.GetNext(), Is.Null);
Assert.That(node1.GetPrevious(), Is.Null);
}
/// <summary>
/// Removes the specified node from the linked list
/// </summary>
/// <param name="node">The node to be removed</param>
/// <returns>Data from the node being removed</returns>
private T Unlink(Node <T> node)
{
Node <T> previous = node.GetPrevious();
Node <T> next = node.GetNext();
previous.SetNext(next);
next.SetPrevious(previous);
size--;
return(node.GetData());
}
/// <summary>
/// Remove the node at the tail of the linked list and return the data it contains
/// </summary>
/// <returns>The data stored in the node being removed</returns>
private T UnlinkTail()
{
Node <T> oldTail = tail;
tail = tail.GetPrevious();
tail.SetNext(null);
size--;
return(oldTail.GetData());
}
/// <summary>
/// Returns the data from the node
/// </summary>
/// <returns>The data from the node</returns>
public T Get()
{
// Determine if linked list size is 0
if (size == 0)
{
throw new IndexOutOfRangeException("No such element");
}
else
{
return(head.GetData());
}
}
/// <summary>
/// Returns the last data item in the linked list.
/// </summary>
/// <returns>The data from the last node</returns>
public T GetLast()
{
// Determine if size of linked list is 0 and throw an exception if it is
if (size == 0)
{
throw new IndexOutOfRangeException("No such element");
}
else
{
return(tail.GetData());
}
}
public void TestAllArgContructor()
{
Employee emp1 = new Employee(1);
Employee emp2 = new Employee(2);
Employee emp3 = new Employee(3);
Node <Employee> node1 = new Node <Employee>(emp1);
Node <Employee> node2 = new Node <Employee>(emp2);
Node <Employee> testNode = new Node <Employee>(emp3, node1, node2);
Assert.That(testNode, Is.Not.Null);
Assert.That(testNode.GetData(), Is.EqualTo(emp3));
Assert.That(testNode.GetNext(), Is.EqualTo(node2));
Assert.That(testNode.GetPrevious(), Is.EqualTo(node1));
}
/// <summary>
/// Returns the data using a value stored in the linked list
/// </summary>
/// <param name="data">Data to look for in the list</param>
/// <returns>Node found containing the data specified</returns>
public T Get(T data)
{
Node <T> node = Find(data);
// Determine if node is null and throw exception if it is
if (node == null)
{
throw new IndexOutOfRangeException("No such element");
}
else
{
return(node.GetData());
}
}
/// <summary>
/// Removes the node at the head of the linked list and returns the data it contains
/// </summary>
/// <returns>The data from the unlinked head node</returns>
private T UnlinkHead()
{
Node <T> oldHead = head;
T data;
head = head.GetNext();
size -= 1;
// Determine if head is now null and if it is make the tail null as well
if (head == null)
{
tail = null;
}
head?.SetPrevious(null);
data = oldHead.GetData();
return(data);
}
