I am porting my Android app to iOS and I am using Codename One for that. In my app an EditText can contain icons mixed with text. It is accomplished with instructions like these: MyImageSpan iconSpan=…
Moving packages in IntelliJ IDEA
I have a problem moving packages in IntelliJ IDEA. I have created Maven project with multiple modules and each of those modules has a package with the same name. Now whole project becomes a mess if I try to rename some of the packages. My current project structure is something like this: Notice that somepacka…
Add new edge to Graph and check if total weight is reduced
I’m new to Graphs and I’m trying to solve this problem in Java: Given a Graph with N nodes and N-1 weighted bidirectional edges, the algorithm must respond YES if a new edge ‘q’ allows to reduce the overall weight of the graph, NO otherwise. The edge ‘q’ satisfies this cond…
Counting Inversions using TreeSet Java
I’m using TreeSet for solving counting inversions problem. I’m using following approach which uses gnu_pbds which works in O(logn) time. Algorithm Insert the first element of the array in the Ordered_Set. For all the remaining element in arr[] do the following: Insert the current element in the Or…
Java happens-before relationship?
Consider the following code. Thread A calls run(), then another thread B calls test() and there shouldn’t be any happens-before relationship. I know it is not guaranteed that thread B sees the changes which thread A made. But is it possible that the output of this program is: Answer Yes, it’s poss…
Program not printing element at index 0
I’m working on case 3 and I need to print some details about the 3 instances for the Airplane class and the BatMobile class. The loop only prints out elements at index 1 and 2 and the other 3 …
What’s the time complexity of this anagram checker?
What is the time complexity of this method? I read that time complexity of contains() method of String is O(n) and I’m using it inside my loop that goes over the input string is the time complexity O(…
How to use OpenCV 4.4.0 (with contrib modules) in Java on Windows?
I’ve compiled OpenCV 4.4.0 from source on Windows 64 bit along with java bindings and I’m trying to compile a basic test, however I’m running into unexpected errors. Here’s how I’ve setup an eclipse project: and this how the jar references the native libraries: And this is the ba…
Storing methods identifiably in Java
I’m trying to come up with a solution to a problem where I want to store method references in some way so that I can invoke them when needed and remove them when I don’t need them on my list of methods. The underlying goal here goes something like this: I have a Person class: I make 2 instances of
Transforming if-else into switch case throws error [Java]
I tried to convert my if-else statements into a switch case but I had the following problem. Old code: New code: First, the String database threw an error that I have to change setting/property (actually don’t know) into version 1.7?! After doing so, my cases are throwing now errors. They say: Type mism…