All Questions
Tagged with functional-programming java
49 questions
5
votes
6
answers
432
views
Search values by priority in a Stream
I have a simple list of results, and I need to return only one value depending on content, for example:
...
- 151
3
votes
1
answer
110
views
In Java, replace for loop with condition with lambdas [closed]
I want to replace a for loop with a break/return condition inside with a lambda.
I think I have a good replacement, but I want ...
5
votes
2
answers
161
views
Print the three most occurring chars in Java using streams
The three characters that occurs most in a given string should be printed by using streams/lambdas (functional programming). The order of characters that occur equally often should be preserved.
My ...
- 762
3
votes
1
answer
108
views
Sequentially find the indexes of an element into a collection
Util class to find into a collection the indexes of a given element with multiple occurrences from the first index or relative to a given index.
...
user277679
2
votes
1
answer
128
views
Stream Partitioner
Discussion
I've been trying to increase my knowledge of Java Streams and for practice, I devised up the requirement of partitioning a Stream of values into a ...
- 1,875
2
votes
2
answers
473
views
A Union Data Type
Introduction
I'm trying to get familiar with functional programming by implementing some functional concepts.
One of these concepts that I've attempted to implement below is a ...
- 1,875
3
votes
2
answers
443
views
Streaming substrings of a string
Given a (long) string src, generate substrings (up to) len characters long on demand by iterating over ...
- 131
3
votes
2
answers
198
views
Compute variance via functional programming
So I'm supposed to calculate variance based on this forumula through functional programming:
$$\sigma^2 = \frac{\sum\limits_{i=0}^{n-1} (X -\mu)^2}{n-1}$$
This is the code that works:
...
- 133
3
votes
1
answer
658
views
Updates or creates an entity based on if a value is present in an Optional
I need to get car info from a 3rd party web service and persist the data in my application DB. If my DB already has the car, I only update property values that may have changed. Otherwise, I create ...
- 289
3
votes
2
answers
5k
views
Hackerrank problem: Climbing the Leaderboard (Java)
I am solving the following Hackerrank problem: Climbing the Leaderboard.
The problem statement:
Alice is playing an arcade game and wants to climb to the top of the leaderboard and wants to track her ...
- 79
3
votes
2
answers
224
views
Creating a new list using a stream
I have a StudentSchedule class that contains schedules of a student, the student may switch between rooms over time. There's no overlap with the date ranges so if a student stops at 2020-01-01 the ...
3
votes
2
answers
162
views
Leap year check in Java (functional style)
I have done the leap year check on https://exercism.io already in a lot of languages. Today I came back to the exercise in Java and was playing around with some maybe more funny ways to do the check. ...
- 233
0
votes
1
answer
107
views
Pure methods for updating java objects
I've been reading about pure methods and immutability in Java. I have a current application and want to convert all the methods to pure methods.
My app takes payment from users. I first create a ...
- 221
2
votes
1
answer
318
views
FizzBuzz with Lambda Expressions in Java
I wanted to create a FizzBuzz in Java that is supposed to be open for extension.
So the initial problem is the good old, if divisible by 3 print fizz, if divisible by 5 print buzz, if divisible by ...
- 1,557
1
vote
3
answers
121
views
Picking from a list of individuals based on their fitness values
I have this method that takes a list of my individuals (class has public field fitnessValue). I sum all fitnessValue and then ...
- 98