public void GetHashCodeShouldBeComputedLazyAndShouldBeVeryFast()
{
var geometryCount = 1000000;
var geometries = new IGeometry[geometryCount];
for (int i = 0; i < geometryCount; i++)
{
geometries[i] = new Polygon(new LinearRing(new[] { new Coordinate(1.0, 2.0), new Coordinate(2.0, 3.0), new Coordinate(3.0, 4.0), new Coordinate(1.0, 2.0) }));
}
var polygon = new Polygon(new LinearRing(new[] { new Coordinate(1.0, 2.0), new Coordinate(2.0, 3.0), new Coordinate(3.0, 4.0), new Coordinate(1.0, 2.0) }));
// computes hash code every call
var t0 = DateTime.Now;
for (int i = 0; i < geometryCount; i++)
{
geometries[i].GetHashCode();
}
var t1 = DateTime.Now;
var dt1 = t1 - t0;
// computes hash code only first time (lazy)
t0 = DateTime.Now;
for (int i = 0; i < geometryCount; i++)
{
polygon.GetHashCode();
}
t1 = DateTime.Now;
var dt2 = t1 - t0;
Assert.IsTrue(dt2.TotalMilliseconds < 15 * dt1.TotalMilliseconds);
}
public void CompareUsingHashcode()
{
var polygon = new Polygon(new LinearRing(new[] { new Coordinate(1.0, 2.0), new Coordinate(2.0, 3.0), new Coordinate(3.0, 4.0), new Coordinate(1.0, 2.0) }));
Assert.AreEqual(495991521, polygon.GetHashCode());
}
