How do I benchmark methods in JMH that is having string parameters, coming from other class?.
#Benchmark
#BenchmarkMode(Mode.All)
#Warmup(iterations = 5, time = 1)
#Measurement(iterations = 2, time = 1)
public refType getOrAdd(String refTypeName)
{
return nameClass.containsValue(refTypeName)
}
When I compile, I am getting the following error:
Method parameters should be either #State classes
Think about it: how JMH is supposed to know with what values to call the #Benchmark method with? Whatever calls that getOrAdd method should feed it with data, and the caller should be the #Benchmark then. Or, it should be something JMH knows about and initializes by itself, for example #State class bearing the parameters, as the compile error suggests.
It is hard to see what you want to accomplish without seeing the rest of the code. Please look up how to create MCVEs.
Related
I'm trying to use function pointers in DLang (Pointer to function), but it wont compile. All the code on the web on making function pointers, doesn't work for me. This is my code:
tqvar function(tqlist)[string] procs;
procs["divide"] = รท/// cannot implicitly convert expression (&this.divide) of type tqvar delegate(tqlist args) to tqvar function(tqlist) (QScript)
tqvar divide(tqlist args){
tqvar result;
result.ii = true;
result.d = args.read(0).d/args.read(1).d;
return result;
};
I'm using dmd2, on ubuntu.
divide is apparently a delegate, not a function. You can either use a list of delegates instead (just replace function with delegate) or ensure your function is not a delegate.
For the latter: it looks like divide is a class method, not a plain function. Either make it static or move it outside of the class body.
I have a method with this signature
public IEnumerable<T> GetAll<T>() where T : new()
{
// Orm Lite Version
return Connection.LoadSelect<T>();
}
At compile time I don't know the Type T. I only know the class name at runtime is it possible to call this method using reflection with something like this?
string TargetTBLName = ...;//TargetTBLName get's it's value at runtime
Type ParentTableClass = Type.GetType(TargetTBLName);
IEnumerable<Type.GetType(TargetTBLName)> test = Repository.GetAll<Type.GetType(TargetTBLName)>();
Any Ideas?
I'd give a Dynamitey library a go. You can do that in many different ways, but I prefer this one because of its simplicity. You can find it here.
var name = InvokeMemberName.Create;
var test = Dynamic.InvokeMember(Repository, name("GetAll", new[]{ParentTableClass }));
foreach(var obj in test)
{
obj.SomeMethodFromMyType();
}
Keep in mind, that if Repository is static, than you have to tweak it a bit to use static invocation context (look up the link).
Now you have a test object, which is a dynamic - you can use it with duck typing (which has some implications on speed, for example), but in general you can do whatever you want to do with a normal IEnumerable<YourType>.
If you want to use reflection:
MethodInfo getAll= typeof(Repository).GetMethod("GetAll");
MethodInfo getAllGeneric= getAll.MakeGenericMethod(ParentTableClass);
object result = getAllGeneric.Invoke(this, null);
//or null, null is Repository is static
var finalObject = result as IEnumerable;
Mind that since this ParentTableClass is an unknown during compilation, you won't have access to anything that the actual type provides - unless you use dynamic approach.
Let's Say I Have This Class:
package{
import flash.display.Sprite;
public class Main extends Sprite{
public function Main(){
trace(getAverage(1,2,3));
trace(getAverage(1,2,3,4));
trace(getAverage(1,2,3,4,5));
}
public function getAverage (...numbers) {
var total = 0;
for (var i = 0; i < numbers.length; i++) {
total += numbers [i];
}
return total / numbers.length;
}
}
}
How do I accomplish the "opposite" of this? Namely, how could I now CALL 'getAverage' with a dynamic number of paraemters?
For instance, if I wanted to do something LIKE:
var r:int=Math.random()*6;
var a:Array=new Array();
for (i:int=0;i<r;i++) {
a[i]=Math.random()*22;
}
// Now I have 'r' Number Of Parameters Stored In 'a'
// How Do I Call getAverage, with all the values in 'a'??
// getAverage(a) isn't right, is it?
// I'm looking for something similar to getAverage(a[0],a[1],a[...]);
var av:Number=getAverage(???);
What I want to know, is if I have a function that takes a variable number of arguments, that's great, but how can I CALL IT with a variable number of arguments, when that number isn't known at runtime? Possibly it's impossible... I'm just not sure, since 'callLater' seems to be able to take an array and generate a dynamic number of parameters from it somehow...
NOTE: Answers consisting solely of "Why Do You Want To Do This?", will be downvoted.
P.S. This IS NOT about calculating Averages! I REALIZE There Are Way Simpler Ways Of Doing All Of This! (I could just write getAverage to accept a single array as its only parameter) The Above is just an EXAMPLE to Illustrate my Question. HOW TO PASS A DYNAMIC NUMBER OF PARAMETERS TO A FUNCTION?
Is this what you're looking for?
var av:Number = getAverage.apply(null, a);
Dave is correct. You can use the apply method of a function to pass in an Array of arguments.
Here is a better explanation of how it works and what the arguments of apply are:
http://www.adobe.com/livedocs/flash/9.0/ActionScriptLangRefV3/Function.html
Also note that you can use the call method to do the same thing but using ...args (comma-delimited list) instead, but apply would be more suitable to your situation.
The problem with your question is that the arguments object is already an Array and using (...args) already provides you with a dynamic way to pass any number of arguments you require. Sorry about the previous answer, wasn't thinking straight...
You can create an array or an object with those parameters and pass that object to that function. That's just normal.
Flash has a rather strong introspection capabilities. So, instead of passing a number of objects, you just pass a single dynamic object with any number of attributes you need:
var ob:Object={arg1:"value1", arg2:8};
var arg:String="arg4";
ob["arg3"]=8;
ob[arg]=18;
trace (ob.hasOwnProperty("arg1"));
trace (ob.arg3);
trace (ob.arg4);
That should cover just about any use case you might need. The downside is that this allows for some rather clever and hard to trace bugs. :-)
I need to log all the function parameters in a dozen functions.
Is there a way to pro grammatically determine all the parameters and their values (or at least their .ToString() value)? Perhaps via reflection?
Here is an example of how to do this with PostSharp
http://consultingblogs.emc.com/merrickchaffer/archive/2009/08/04/using-postsharp-to-log-method-entry-and-exit-in-net-code.aspx
You can also roll your own
http://www.developerfusion.com/article/5307/aspect-oriented-programming-using-net/3/
To the best of my knowledge there's no way to use reflection to dynamically list and determine value of local variables. You can use reflection to get type information about the parameters of a method, but only the declared type - you can't automatically get information about the actual arguments, because the reflection metadata gives information about the method definition, not the specific values passed to it at runtime.
You can, however, do something like this:
static class Extensions
{
public static string GetTypeAndValue(this object obj)
{
return String.Format("{0}: {1}", obj.GetType().Name, obj.ToString());
}
}
Then, from within each method in which you want to perform logging, do something like
private void SomeMethodToBeLogged(string some_string, int some_int, bool some_bool)
{
Logger.Log(String.Format("SomeMethodToBeLogged({0}, {1}, {2})",
some_string.GetTypeAndValue(),
some_int.GetTypeAndValue(),
some_bool.GetTypeAndValue()));
}
I have a testing scenario where I want to check if two collections are equal. I have found the class Microsoft.VisualStudio.QualityTools.UnitTesting.CollectionAssert, but it only works on ICollection<T>. Since I'm testing a repository for Entity Framework, and thus need to compare IObjectSet<T>s, that won't do - IObjectSet<T> doesn't implement ICollection<T>.
Is there any way I can use this class to compare the collecitons, or do I have to create my own implementation? (And why the heck didn't the Microsoft team make the class work with IEnumerable<T> instead, as that is the "base interface" for collections?)
EDIT: This is my test code:
// Arrange
var fakeContext = new FakeObjectContext();
var dummies = fakeContext.Dummies;
var repo = new EFRepository<DummyEntity>(fakeContext);
// Act
var result = repo.GetAll();
// Assert
Assert.IsNotNull(result, NullErrorMessage(MethodName("GetAll")));
Assert.IsInstanceOfType(result, typeof(IEnumerable<DummyEntity>), IncorrectTypeMessage(MethodName("GetAll"), typeof(IEnumerable<DummyEntity>)));
CollectionAssert.AreEqual(dummies.ToList(), result.ToList());
The CollectionAssert.AreEqual call on the last line fails, stating that the elements at index 0 are not equal. What am I doing wrong?
A cheeky option (not quite as much info though) is to assert that expected.SequenceEqual(actual) returns true.
You could write a wrapper method that forces a collection (.ToList() on each)? But to be honest you might as well just call .ToList() in the unit test code:
CollectionAssert.AreEqual(expected.ToList(), actual.ToList()); // but tidier...
If you're comparing result sets you might want to use CollectionAssert.AreEquivalent which will ignore the order. You should also make sure you have implemented Equals on the type of elements you are comparing.