How can we lower the time complexity of this solution of NxN queens matrix validator? I have this solution while I check every row and every column and every diagonal of the matrix. If every row and column has exactly 1 queen, and the matrix has no more than 1 queen the output is true. This solution works but…
Tag: java
How to get first parameter from each 2D-array data in android studio using java
I have a String 2D-array named items in my app like this : and I want to have a String ArrayList that include first parameter of each item data, something like this : i used this code but unfortunately it didn’t work Answer You can also use streams to build this list: If you still want to use a for
How to stop the loop executing n times?
i’m having an issue where I would like the below code to add the specified elements from the first array to the new array at the given indexes. However, the problem is that the loop with not exit. For eg. The below should print items at index 4 and 5 and then exit as the array only has items indexed
Executing Spring AOP aspects for annotations aliased with @AliasFor
The idea is to create annotations hierarchy (similar to @Service, @Component etc) using @AliasFor annotation. This should give me the possibility to define aspect, that would execute on parent annotation, and every alias of it. But somehow it doesn’t work for me. @ComponentScan is fine, @EnableAspectJAu…
Spring Data Jpa Repository not saving entities to database
Im having some difficulties using jpa. Im not getting any exceptions, but I cant save anything to the database. I went from Hibernate to Jpa and everything worked perfectly there. Below are my Files application.properties: Model: Repository: Service: I’m getting a 200 Response when submitting the form, …
Android 12 – Fatal Exception: android.content.res.Resources$NotFoundException
I’m getting the below error on Android 12 devices. Any help is highly appreciated. Thanks in Advance. Answer This is an upstream bug on Android 12 + Samsung devices, Chromium team and Samsung are aware. Star this issue to follow along: https://bugs.chromium.org/p/chromium/issues/detail?id=1271617 Until …
android firebase start listing data equal to entered letter
There is a problem with the list inside the “if” it doesn’t work I get an error this:java.lang.ClassCastException: java.lang.String cannot be cast to java.util.List Answer You are getting the following error: java.lang.ClassCastException: java.lang.String cannot be cast to java.util.ListR…
Loop Object from a single Array
im sending a Json Array from Activity A to Activity B, and i want to populate that Json Array into Spinner in Activity B. but when i Log the json array from Activity A, the data becomes a single object “NVAKSINATOR” : [{“NVAKSINATOR”:”[{“NVAKSINATOR”:”20800̸…
How to format log4j timestamp with nanoseconds and timezone?
I want to achieve a timestamp that has nanoseconds and time zone difference, example: 2021-11-30 22:21:41.829798+02:00 I failed with variations like: %d{yyyy-MM-dd HH:mm:ss.nnnnnnXXX} Dependency: Is that supported with log4j and if so how can I achieve that? thanks. Answer I was able to find an obvious soluti…
How can I display checkboxes instead of boolean in vaadin grid?
I’m working on a new application using vaadin-spring-boot-starter 21.0.7 and trying to render training database information in a Grid. I’d like to have the first column in the list be a checkbox for Active/Inactive, but I can’t figure out how to get that done. Everything I’ve seen has …