They aren’t semantically identical. The NameValueCollection can have duplicate keys while the Dictionary cannot. Personally if you don’t have duplicate keys, then I would stick with the Dictionary. It’s more modern, uses IEnumerable<> which makes it easy to mingle with Linq queries. You can even create a Dictionary using the Linq ToDictionary() method.
Lots of potential solutions, but let’s add just one more. Use Jackson (JSON processing lib) to do “json-less” conversion, like: ObjectMapper m = new ObjectMapper(); Map<String,Object> props = m.convertValue(myBean, Map.class); MyBean anotherBean = m.convertValue(props, MyBean.class); (this blog entry has some more examples) You can basically convert any compatible types: compatible meaning that if you did … Read more
Decompiling the source for the Count() extension method reveals that it tests whether the object is an ICollection (generic or otherwise) and if so simply returns the underlying Count property: So, if your code accesses Count instead of calling Count(), you can bypass the type checking – a theoretical performance benefit but I doubt it … Read more
if you don’t mind using NumPy (which comes with your Python(x,y)), you may want to look at the np.testing module which defines, among others, a assert_almost_equal function. The signature is np.testing.assert_almost_equal(actual, desired, decimal=7, err_msg=”, verbose=True) >>> x = 1.000001 >>> y = 1.000002 >>> np.testing.assert_almost_equal(x, y) AssertionError: Arrays are not almost equal to 7 decimals … Read more
The 2-parameter version of Collectors.toMap() uses a HashMap: public static <T, K, U> Collector<T, ?, Map<K,U>> toMap( Function<? super T, ? extends K> keyMapper, Function<? super T, ? extends U> valueMapper) { return toMap(keyMapper, valueMapper, throwingMerger(), HashMap::new); } To use the 4-parameter version, you can replace: Collectors.toMap(Function.identity(), String::length) with: Collectors.toMap( Function.identity(), String::length, (u, v) -> … Read more
There are four alternatives that I know of. The first is Channels, which provides a threadsafe queue that supports asynchronous Read and Write operations. Channels are highly optimized and optionally support dropping some items if a threshold is reached. The next is BufferBlock<T> from TPL Dataflow. If you only have a single consumer, you can … Read more
In C#, there are three concepts for representing a bag of objects. In order of increasing features, they are: Enumerable – unordered, unmodifiable Collection – can add/remove items List – allows items to have an order (accessing and removing by index) Enumerable has no order. You cannot add or remove items from the set. You … Read more
OK, here is my attempt (building on Jon’s – thanks), archived here and open for improvement : /// <summary> /// This is a dictionary guaranteed to have only one of each value and key. /// It may be searched either by TFirst or by TSecond, giving a unique answer because it is 1 to 1. … Read more
One difference is that conj accepts any number of arguments to insert into a collection, while cons takes just one: (conj ‘(1 2 3) 4 5 6) ; => (6 5 4 1 2 3) (cons 4 5 6 ‘(1 2 3)) ; => IllegalArgumentException due to wrong arity Another difference is in the class … Read more
The first one is useful when you need the index of the element as well. This is basically equivalent to the other two variants for ArrayLists, but will be really slow if you use a LinkedList. The second one is useful when you don’t need the index of the element but might need to remove … Read more