34,568 questions
-3
votes
0
answers
96
views
Mismatch in Java version or why is this error showing up? [closed]
In VS code whenever I declare an ArrayList like
List<Integer> myList = new ArrayList<>();
It gives the following compilation error:
incompatible types: cannot infer type arguments for ...
0
votes
1
answer
123
views
Make array of Variables with osclass custom category values
How can i make an array of veriables generated using the values passed through a while loop
I am using osclass for a uni project and i find no way whatsoever to make a list os usable variables from ...
- 9
1
vote
1
answer
71
views
Framing verification issue on mutable array in a typical ArrayList Insert operation
Consider the following simple ArrayList implementation:
class ArrayListImpl<T(0)> {
var xs: array<T>
var n: nat
predicate Valid() reads this
{ 0 <= n <= xs.Length }
...
- 5,488
3
votes
3
answers
161
views
How to consistently retain an exact percentage of elements from a List in Java?
I'm currently filtering a Java List to keep approximately a percentage of its elements using a random approach:
import java.util.List;
import java.util.Random;
public class Main {
public static ...
- 33
1
vote
1
answer
84
views
Trying to create nested lists of text data based on test group and questionnaire response, then return the total number of each type of response
My macro accurately creates 2 lists of numerical data based on which group (control or exposed) a subject is in.
Dim Subjects As Integer
Subjects = Sheets("Participant Info").Range("C4:...
- 31
1
vote
1
answer
62
views
Excel Macro only returns last value in an array
I have a list of 36 subjects and their ages, and whether they are in the 'Control' or "Exposed" group. I am trying split this list into two based on what group they are in. The program ...
- 31
3
votes
3
answers
332
views
ArrayList vs LinkedList in terms of cache locality
How does cache locality impact the performance of ArrayList compared to LinkedList in Java?
I've often heard that ArrayList has an advantage in terms of cache locality, but I don't fully understand ...
- 73
0
votes
1
answer
71
views
Backtracking confusion
Concerning Javascript, I've been trying to understand backtracking lately and it's really confusing. Specifically, I've been trying to understand the permutation problem, which when given an array, we ...
3
votes
2
answers
169
views
How to retrieve individual arrays from arrays of strings stored inside an ArrayList?
I'm working on an assignment where I need to take "books" from the user(a title, an author, and ISBN number, all strings), and store these books somehow, and then do various things to these ...
- 33
1
vote
1
answer
46
views
LINQ Query to find items that contain a value in an array of values
I have a text property in a class that will contain multiple words along with other properties (index, linenumber, starttime, endtime). I have an arraylist (rawdata) of that class built.
I need to be ...
- 13
1
vote
1
answer
76
views
Java with Playwright onResponse method - can't get returned String value, IndexOutOfBoundsException
I have created a void method which prints out the required responses from an url (using Java and Playwright) but I actually need to receive these values for making junit assertions and I am trying to ...
- 85
2
votes
3
answers
259
views
What does this piece of code mean? new ArrayList<>(Collections.emptyList())
In some code from my company, I've read a list initialization:
List<SomeClass> someClassList = new ArrayList<>(Collections.emptyList())
What does it mean? A list with 0 size ...
- 361
0
votes
1
answer
61
views
Stack Overflow on Quicksort with a first element pivot in Java
For this assignment I'm supposed to test my quicksort class using a variety of different pivots and a variety of ArrayLists in different arrangements. The class works fine with a random pivot, or a ...
- 19
2
votes
3
answers
91
views
How to check if the user has purchased the maximum capacity?
I have a Java code for booking movie tickets. In this program, each person can only buy two tickets, a maximum of 10 tickets are sold and at the end it displays a list with the names of the people. I ...
- 33
0
votes
0
answers
49
views
Drools - Pulling an ArrayList<String> from a HashMap<String, Object> in drools
For the life of me I cannot pull a simple String ArrayList from my generic hashmap: HashMap<String, Object>
I have been able to pull much more complicated structures such as List of objects ...
- 23