public void GenericsTypeSafety() //Generics types allow code reuse with type safety and Performance benefits
{
var dovesList = new List<Dove>(); //A List<T> is a Type that has one implementation but can work with any Object
var firstDove = new Dove();
var secondDove = new Dove();
dovesList.Add(firstDove);
dovesList.Add(secondDove);
// dovesList.Add("StringDove"); This fails at compile time since the List<Dove> can only accept Doves
Assert.AreEqual(true, dovesList.Any());
}
public void GetShortestRoute_should_consider_routes_in_order_from_small_distance()
{
using (new IndirectionsContext())
{
// Arrange
var slot = 0;
var numAndDistances = new[] { 4, 2, 4, 3, 1, 6, 7 };
PRandom.NextInt32().Body = (@this, maxValue) => numAndDistances[slot++];
var vil = new Village();
var considerations = new List<RicePaddy>();
PList<RicePaddy>.AddT().Body = (@this, item) =>
{
IndirectionsContext.ExecuteOriginal(() =>
{
considerations.Add(item);
@this.Add(item);
});
};
// Act
var result = vil.GetShortestRoute(vil.RicePaddies.ElementAt(2), vil.RicePaddies.ElementAt(0));
// Assert
Assert.AreEqual(3, result.TotalDistance);
Assert.AreEqual(4, considerations.Count);
Assert.AreEqual(2, considerations[0].Identifier);
Assert.AreEqual(1, considerations[1].Identifier);
Assert.AreEqual(0, considerations[2].Identifier);
Assert.AreEqual(3, considerations[3].Identifier);
}
}
public void TestValueTypePerformace()
{
using (new OperationTimer("List<int>"))
{
var l = new List<int>(Count);
for (int i = 0; i < Count; i++)
{
l.Add(i);
int x = l[i];
}
l = null;
}
using (new OperationTimer("ArrayList of In32"))
{
var a = new ArrayList(Count);
for (int i = 0; i < Count; i++)
{
a.Add(i);
int x = (int)a[i];
}
a = null;
}
}
public void TestReferenceTypePerformance()
{
using (new OperationTimer("List<string>"))
{
var l = new List<string>(Count);
for (int i = 0; i < Count; i++)
{
l.Add("X");
string x = l[i];
}
l = null;
}
using (new OperationTimer("ArrayList of String"))
{
var a = new ArrayList(Count);
for (int i = 0; i < Count; i++)
{
a.Add("X");
string x = (string)a[i];
}
a = null;
}
}
static void Main(string[] args)
{
MyCollection<int> intCollection = new MyCollection<int>(2, 6);
intCollection.Add(3);
for(int i=0;i<intCollection.Count();i++)
Console.WriteLine(intCollection[i]);
intCollection.Sort();
Console.WriteLine("После сортировки:");
for (int i = 0; i < intCollection.Count(); i++)
Console.WriteLine(intCollection[i]);
int newInt = intCollection.CreateEntity();
Console.WriteLine("создали число "+newInt);
//коллекция котов
MyCollection<Cat> catCollection = new MyCollection<Cat>();
catCollection.Add(new Cat { Name = "Мурка", Weight = 8 });
catCollection.Add(new Cat { Name = "Мурзик", Weight = 15 });
catCollection.Add(new Cat { Name = "Барсик", Weight = 10 });
for (int i = 0; i < catCollection.Count(); i++)
Console.WriteLine(catCollection[i]);
catCollection.Sort();
Console.WriteLine("После сортировки:");
for (int i = 0; i < catCollection.Count(); i++)
Console.WriteLine(catCollection[i]);
foreach (Cat cat in catCollection)
Console.WriteLine(cat);
Cat newCat = catCollection.CreateEntity();
Console.WriteLine("Создали кота "+newCat);
DateTime time1 = DateTime.Now;
ArrayList arrList = new ArrayList();
for (int i = 0; i < 1000000;i++ )
{
arrList.Add(i);//упаковка
int x =(int) arrList[i];//распаковка
}
Console.WriteLine((DateTime.Now-time1).TotalSeconds);
arrList.Add("Вася");
DateTime time2 = DateTime.Now;
List<int> list = new List<int>();
for (int i = 0; i < 1000000; i++)
{
list.Add(i);
int x = list[i];
}
//list.Add("Вася");
Console.WriteLine((DateTime.Now - time2).TotalSeconds);
Console.ReadKey();
}
// We will get the shortest path between the begin RicePaddy and the end RicePaddy by Dijkstra's algorithm.
Dictionary<RicePaddy, Route> CalculateShortestRoutes(RicePaddy start)
{
var shortestRoutes = new Dictionary<RicePaddy, Route>();
var handled = new List<RicePaddy>();
foreach (var ricePaddy in m_ricePaddies)
{
shortestRoutes.Add(ricePaddy, new Route(ricePaddy.Identifier));
}
shortestRoutes[start].TotalDistance = 0;
while (handled.Count != m_ricePaddies.Count)
{
var shortestRicePaddies = shortestRoutes.OrderBy(_ => _.Value.TotalDistance).Select(_ => _.Key).ToArray();
var processing = default(RicePaddy);
foreach (var ricePaddy in shortestRicePaddies)
{
if (!handled.Contains(ricePaddy))
{
if (shortestRoutes[ricePaddy].TotalDistance == int.MaxValue)
return shortestRoutes;
processing = ricePaddy;
break;
}
}
var selectedRoads = m_roads.Where(_ => _.A == processing);
foreach (var road in selectedRoads)
{
if (shortestRoutes[road.B].TotalDistance > road.Distance + shortestRoutes[road.A].TotalDistance)
{
var roads = shortestRoutes[road.A].Roads.ToList();
roads.Add(road);
shortestRoutes[road.B].Roads = roads;
shortestRoutes[road.B].TotalDistance = road.Distance + shortestRoutes[road.A].TotalDistance;
}
}
handled.Add(processing);
}
return shortestRoutes;
}
public void GenericsPerformanceGains() //Generics perform so much better than normal collections
{
const int iterations = 10000000;
var stopwatch = new Stopwatch();
stopwatch.Start();
var list = new ArrayList();
for (var currentIteration = 0; currentIteration <= iterations; currentIteration++)
{
list.Add(currentIteration);
}
foreach (var value in list.Cast<int>()) //We need to perform a cast in every member of the list
{
}
stopwatch.Stop();
var arrayListMilliseconds = stopwatch.ElapsedMilliseconds;
stopwatch.Reset();
stopwatch.Start();
var intList = new List<int>();
for (var currentIteration = 0; currentIteration <= iterations; currentIteration++)
{
intList.Add(currentIteration); //No cast is required
}
foreach (var integer in intList)
{
var value = integer;
}
stopwatch.Stop();
var listMilliseconds = stopwatch.ElapsedMilliseconds;
//List<T> will always outperform ArrayList, CLR performs internal optimizations as well
Assert.IsTrue(arrayListMilliseconds > listMilliseconds);
}
private static List<string> GetNamesOfCodeFilesInProjectDirectory()
{
string path = Directory.GetCurrentDirectory();
string[] files = Directory.GetFiles(path + @"\..\..", "*.cs");
var fileNames = new List<string>();
foreach (var s in files)
{
FileInfo fileInfo = new FileInfo(s);
if (!fileInfo.Name.Equals("Program.cs"))
fileNames.Add(fileInfo.Name.Substring(0, fileInfo.Name.Length - 3));
}
fileNames.Sort();
return fileNames;
}
