In C#, I want to initialize a string value with an empty string. How should I do this? What is the right way, and why? string willi = string.Empty; or string willi = String.Empty; or string willi = “”; or what? 30 s 30 Use whatever you and your team find the most readable. Other … Read more
I need to create a Set with initial values. Set<String> h = new HashSet<String>(); h.add(“a”); h.add(“b”); Is there a way to do this in one line of code? For instance, it’s useful for a final static field. 24 s 24 There is a shorthand that I use that is not very time efficient, but fits … Read more
In Hidden Features of Java the top answer mentions Double Brace Initialization, with a very enticing syntax: Set<String> flavors = new HashSet<String>() {{ add(“vanilla”); add(“strawberry”); add(“chocolate”); add(“butter pecan”); }}; This idiom creates an anonymous inner class with just an instance initializer in it, which “can use any […] methods in the containing scope”. Main question: … Read more
In Hidden Features of Java the top answer mentions Double Brace Initialization, with a very enticing syntax: Set<String> flavors = new HashSet<String>() {{ add(“vanilla”); add(“strawberry”); add(“chocolate”); add(“butter pecan”); }}; This idiom creates an anonymous inner class with just an instance initializer in it, which “can use any […] methods in the containing scope”. Main question: … Read more
If ‘Test’ is an ordinary class, is there any difference between: Test* test = new Test; and Test* test = new Test(); 7 s 7 Let’s get pedantic, because there are differences that can actually affect your code’s behavior. Much of the following is taken from comments made to an “Old New Thing” article. Sometimes … Read more
I have a large array in C (not C++ if that makes a difference). I want to initialize all members of the same value. I could swear I once knew a simple way to do this. I could use memset() in my case, but isn’t there a way to do this that is built right … Read more
How would you initialise a static Map in Java? Method one: static initialiser Method two: instance initialiser (anonymous subclass) or some other method? What are the pros and cons of each? Here is an example illustrating the two methods: import java.util.HashMap; import java.util.Map; public class Test { private static final Map<Integer, String> myMap = new … Read more
Is there some way of initializing a Java HashMap like this?: Map<String,String> test = new HashMap<String, String>{“test”:”test”,”test”:”test”}; What would be the correct syntax? I have not found anything regarding this. Is this possible? I am looking for the shortest/fastest way to put some “final/static” values in a map that never change and are known in … Read more
Which method of checking if a variable has been initialized is better/correct? (Assuming the variable could hold anything (string, int, object, function, etc.)) if (elem) { // or !elem or if (typeof elem !== ‘undefined’) { or if (elem != null) { 3 31
I wanted to create a list of options for testing purposes. At first, I did this: ArrayList<String> places = new ArrayList<String>(); places.add(“Buenos Aires”); places.add(“Córdoba”); places.add(“La Plata”); Then, I refactored the code as follows: ArrayList<String> places = new ArrayList<String>( Arrays.asList(“Buenos Aires”, “Córdoba”, “La Plata”)); Is there a better way to do this? 3 33
