Questions tagged [java]
Java (not to be confused with JavaScript) is a class-based, object-oriented, strongly typed, reflective language and run-time environment (JRE). Java programs are compiled to bytecode and run in a virtual machine (JVM) enabling a "write once, run anywhere" (WORA) methodology.
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A simple probabilistic AI for generating random sentences in Java
Motivation
I have this repository. It contains a program that analyzes an input text file and builds a word graph: in the graph, each node represents a word in the analyzed text. Now, if there are two ...
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0
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20
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Payment Service with Java, Spring [closed]
At the interview, they gave such a code, it was necessary to find flaws
...
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3
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3
answers
99
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IPv4 filter in Java
I have a simple class for representing IPv4-addresses via int values, and a simple IP-address filter that works like a set of IPv4-addresses.
...
- 26.5k
3
votes
1
answer
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Calculator (Java/Beginner)
I finished my first calculator using Java!
I try to apply Object-Oriented Programming!
I'll add my gitHub link if you're suited to viewing code on gitHub.
Here is a link to my GitHub Calculator ...
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2
votes
3
answers
411
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Recursive palindrome check
I'm trying to solve this which basically calls for a recursive palindrome check with some minor extra steps (Special characters and whitespace can be ignored). The test inputs' length can be 100000 ...
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0
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Print columns of text without hard coding the width (attempt 4)
If you'd like to print this:
One Two Three Four
1 2 3 4
using this:
...
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0
votes
0
answers
37
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Print columns of text without hard coding the width (attempt 3)
If you'd like to print this:
One Two Three Four
1 2 3 4
using this:
...
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4
votes
1
answer
211
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Print columns of text without hard coding the width (attempt 2)
If you'd like to print this:
One Two Three Four
1 2 3 4
using this:
...
- 794
5
votes
2
answers
64
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Recipe search exercise
I'm currently following Java moocfi Helsinki course.
This is my current assignment :
In this exercise we are going to create a program that allows for searching for recipes based on their name, ...
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3
votes
1
answer
80
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Print columns of text without hard coding the width
If you'd like to print this:
One Two Three Four
1 2 3 4
using this:
...
- 794
3
votes
1
answer
120
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My First Java Battleship Simulator (single array, single ship)
I'm new to this community and also to Java programming!
I recently picked up "Head First Java" and I did my Battleship project.
If you could kindly, give me feedback on the code?
...
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5
votes
2
answers
218
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Select the type of triangle based on the input
I am trying to see if there is a way to improve my code this program ask for 3 number and calculate the what type of triangle it is
...
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2
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0
answers
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Testing CRUD ops with some special cases using Cucumber
Question
Using Cucumber and Java17, I refactored functional tests for a basic CRUD app as I found the previous tests using special variables for different test scenarios and I felt they were brittle ...
- 121
2
votes
1
answer
72
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Java program for complex math utilities
I've got 2 Java programs, with the aim of solving some matrix math that involves complex numbers (an EE problem). Both programs have main functions, the one with all the complex math operations has a ...
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1
vote
3
answers
73
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Extensible error code infrastructure
I was answering a question, Java Exception Error Enumerations Anti-pattern, on Software Engineering Stack Exchange and found myself writing up a fair bit of code. It could use a code review so I'm ...
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0
votes
0
answers
22
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Fee Challan as a practice in Java Swing,
I have made three classes and I have put all the UI code in a different class and used method for labels, text fields etc so it does not mix up. Please look into this code and tell me is it good ...
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8
votes
1
answer
143
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Java code for generating 16bit DMX values using sine and cosine
This is my try, based on good inputs from different places.
I ended up saving the DMX-values in two arrays (one for sine and one for cosine) as I guess that will make stuff easier later on when I want ...
- 83
0
votes
1
answer
65
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Reversing in between a linked list
I have written code for this leetcode problem :-
Given the head of a singly linked list and two integers left and right where left <= right, reverse the nodes of the list from position left to ...
8
votes
2
answers
2k
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1
vote
0
answers
86
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Making Robert Tarjan's offline LCA algorithm run (much) faster (Java)
I have produced this GitHub repository that compares the performance of:
Robert Tarjan's off-line lowest common ancestors algorithm,
An improvement of the above algorithm.
Typical demo program ...
- 26.5k
5
votes
1
answer
269
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Merge multiple map with java stream api
I am trying to merge multiple map with Java stream API.
The reqiurements like ...
this method can receive multiple map, does not care hot many of it
support 2 merge method: intersection, union
if key ...
- 321
0
votes
0
answers
65
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An extended simple, funny, easy linked stack of lists in Java
This post is the continuation of A simple, funny, easy linked stack of lists in Java.
What's new:
Now I have varargs for pushing/linking multiple values per call.
Provided the unit tests.
...
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0
votes
0
answers
54
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A simple, funny, easy linked stack of lists in Java
(See also the next iteration.)
(This data structure can be implemented as Deque<List<T>>, yet I decided to have some better time with it. :-))
...
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0
votes
0
answers
59
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Bruteforce proof of an arithmetic expansion scheme expression in array lists (Java)
Given a list of, say, integers, one way to implement such a list is to rely on an array under the hood. When we are adding elements to the array list, we might need to make the internal array larger. ...
- 26.5k
4
votes
1
answer
273
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Hangman game, with secret word provided by user
I recently started learning programming and in particular Java. I wrote this small hangman game which takes the input for the secret word from the user.
It all works as intended; I would like to know ...
2
votes
2
answers
152
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Quick Sort Program
Quick sort is a sorting algorithm in which we select any random element as pivot from the array and we do the partition of the array around that pivot. Basically we place all the elements smaller than ...
3
votes
0
answers
59
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JavaFX dialog for numeric typed data input
I have this small subclass of JavaFX's javafx.scene.control.Dialog that requires the enum specifying the data type of the input data:
...
- 26.5k
-3
votes
1
answer
104
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Default food property wording when translation not available
I have food table having number of foods, each food can have specific properties in multiple languages (en, es) like name, description etc. But it is not sure if all of the properties are always ...
2
votes
1
answer
55
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Merge Sort with Minimum Sufficient Variables, Verbosity and better Space Complexity
The majority of merge sort implementations searched online are provided with unnecessary variables and code lines. Here is an attempt to reduce that. However, does passing back the subArray as return ...
- 459
1
vote
1
answer
105
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Interconnect Recipe and Notes
I'm currently working through a tutorial. The project is a recipe website.
One of the lessons to "save some lines of code" and use bidirectional setters for bidirectional relations of ...
- 119
0
votes
1
answer
65
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Implement code to monitor file delete action
I have this Java code which I want to use to monitor file changes into directory:
...
- 343
1
vote
0
answers
41
views
Spring boot shop application with error handling
I'm writing a simple online shop using spring boot, for learning purposes. Right now I have purchasing-service and a product-service. The purchasing-service makes requests to the product-service via ...
- 243
0
votes
1
answer
79
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Printing Permutations
Following is a leetcode problem:
Given an array nums of distinct integers, return all the possible permutations. You can return all the possible permutations. You can return the answer in any order.
...
0
votes
1
answer
57
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Delayed, concurrent event stack in Java - follow-up
I have slightly refactored the Delayed, concurrent event stack in Java. Now it looks like this:
DelayedEventStack.java
...
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0
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3
answers
185
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Delayed, concurrent event stack in Java
(See the next iteration:
Delayed, concurrent event stack in Java - follow-up )
Motivation
I was confronted with a task of having "message events" for a GUI program. The use case is as ...
- 26.5k
4
votes
2
answers
179
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Multiplayer queue optimisation
I currently have code that is working but I think it can be optimised.
The code waits until a player joins and adds the player to a BlockingQueue if there is
not already a Player waiting then it ...
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0
votes
1
answer
71
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First try at Java annotations and using them to change instance values
I was curious on how annotations are used during runtime, so after some googling I gave it a try, but kinda have the feeling that is not the proper way as I still have to call the annotation helper on ...
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1
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65
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How can I refactor getAll() method for the service business logic? [closed]
I'm working with the following project, where I have business-logic as:
...
- 121
3
votes
1
answer
85
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Company management app: Extracting data with JDBC and java.sql
I'm currently working on a company management system as a university project, and I have to get my hands in java.sql.
I have come to struggle with extracting a ...
0
votes
0
answers
55
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How to refactor findAll() for finding products method in more proper way?
I'm working with the following code snippet of the ProjectController class as below:
...
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4
votes
2
answers
107
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Designing a basic Binary Expression Tree structure
Preface
I need to generate some algebraic expressions for math testing in elementary school. The test should generate a list of expressions compiled according to certain rules and check the ...
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-2
votes
1
answer
165
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Number Plate Generation Program
I wrote a number plate generation program. The program generates number plates for a car registered with a specific Memory Tag and on a specific date.
Number plates use the following format: (2 letter ...
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1
vote
0
answers
88
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Restaurant Management follows MVC pattern
I am writing the Restaurant Management homework which must be following the MVC pattern. My Menu model has two parts: Drink menu and Food menu.
With Food menu, it separates into three different types ...
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3
votes
1
answer
90
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An encryption/decryption program with two different algorithms, Caesar Cipher and a Unicode Cipher
This project was part of the JetBrains Academy Java course. The project was about implementing an Encryption program that uses either a simple Caesar Cipher (or) a Unicode Cipher depending on the ...
- 133
1
vote
2
answers
87
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Having a separate validation util for common checks
I am working on a project where I see the following methods wrapped in a Util class
...
- 608
4
votes
1
answer
168
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Find largest number of collinear points
The following is my submission for LeetCode's Max Points on a Line:
Given an array of points where points[i] = [xi, yi] represents a point
on the X-Y plane, return the maximum number of points that ...
- 141
1
vote
3
answers
73
views
FileIO lines to String Converter
I think I made a good FileIO object because I can simply copy-paste whenever I need, however I wonder How I can improve my code.
This code takes file path of the target file and turns every line to ...
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0
votes
2
answers
153
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Functional Style if/else in java
I would like to ask the opinion for experts out there. The following code snippet was written by a colleague of mine who is very fond of functional style in Java.
...
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6
votes
4
answers
2k
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Printing a Hollow Butterfly pattern
I am a beginner to Java and have studied up to loops only. After loops lecture above pattern was given to print as homework. I have successfully managed to print this pattern with following code:
<...
1
vote
1
answer
51
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Take meal orders from breakfast, lunch and dinner menus
I have an exercise requires me to write a service to management menu.
The requirement like this:
Food menu includes: breakfast menu, lunch menu, dinner menu. The three menu haves list menu item( name, ...
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