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Tag: java

Merge lists with stream API

I have the following situation I have to merge all the lists lst from the ListContainer objects from a Map map. Any idea how, using Java 8 stream API? Answer I think flatMap() is what you’re looking for. For example:

Unit testing of a shuffle method on a list

Consider the following class: How would I unit test the shuffle() method? I am using JUnit 4 for testing. I have the following options: Test shuffle() to see that it does not generate an exception. Test shuffle() and check if the deck actually gets shuffled. Example pseudocode of option 2: The only culprit he…

How to increment time every second in Libgdx

I try to add time to my game that will increment every second. How to fix that? I add my code below as your note, delta is Gdx.graphics.getDeltaTime(). ‘time’ is string. but looks like the time increment slowly. means that when time already run about 1,5 sec, ‘time’ still increase 1. I…

Derby: Another instance of Derby may have already booted the database

I would like to use Derby in a Network Server Mode and followed the instructions on their website. Starting derby: Connecting with ij: Connecting to Derby in Java: The DriverManager.getConnection() is failing with: Haven’t I just started derby in network server mode? Why am I getting this error? Answer …

Converting C++ code to JAVA

I have to convert my code to Java Code I already converted but i couldn’t find my mistake i cannot point variables to each other.. This is my java code when i look at the int sum1 = (i / 2) + fun(k.value=i); int sum2 = fun(k.value=j) + (j / 2); part isn’t true about point to true values. How

Why do java intrinsic functions still have code?

There are many methods in the Java API that are intrinsics, but still have code associated with them when looking at the source code. For an example, Integer.bitCount() is an intrinsic, but if you open the Integer class file, you can see code with it. What purposes might this code serve if it is not necessari…