A bit old, but here is a deadly simple solution. The idea is simply to render the collection items through a Twig template, so you have full ability to customize the prototype that will be placed in your data-prototype=”…” tag. Just as if it was a normal, usual form. In yourMainForm.html.twig: <div id=”collectionContainer” data-prototype=” {% … Read more
java.util.Collections.enumeration(set) Javadoc Returns an enumeration over the specified collection. This provides interoperability with legacy APIs that require an enumeration as input.
Using Stream: // int[] nums = {1,2,3,4,5} Set<Integer> set = Arrays.stream(nums).boxed().collect(Collectors.toSet())
Because they did it in a hurry in the early days of Java, and didn’t realise what the implications would be four versions later. Generics were supposed to be part of the design of Java from the beginning, but the feature was dropped as being too complicated and, at the time, unnecessary. As a result, … Read more
Others have already pointed out why it is questionable from a mathematical point of view, by referring to Russell’s paradox. This does not answer your question on a technical level, though. So let’s dissect this: First, once more the relevant part from the JavaDoc of the Set interface: Note: Great care must be exercised if … Read more
Performance. If you want the original insertion order there are the LinkedXXX classes, which maintain an additional linked list in insertion order. Most of the time you don’t care, so you use a HashXXX, or you want a natural order, so you use TreeXXX. In either of those cases why should you pay the extra … Read more
You can create a new instance using the existing List in the constructor. var readOnlyList = new ReadOnlyCollection<string>(existingList); ReadOnlyCollection(Of T) Constructor on MSDN
The map holds unique keys. When you invoke put with a key that exists in the map, the object under that key is replaced with the new object. Hence the size 1. The difference between the two should be obvious: in a Map you store key-value pairs in a Set you store only the keys … Read more
If you need to remove elements then you must iterate backwards so you can remove elements from the end of the list: var data=new List<string>(){“One”,”Two”,”Three”}; for(int i=data.Count – 1; i > -1; i–) { if(data[i]==”One”) { data.RemoveAt(i); } } However, there are more efficient ways to do this with LINQ (as indicated by the other … Read more
Guava’s CacheBuilder class allows you to do this easily. CacheBuilder.newBuilder().weakKeys().build() Note that this changes key equality semantics to be == instead of .equals() which will not matter in your case of using Class instances but is a potential pitfall.