I have recently encountered an unusual problem with Garbage Collecter allocation when beginning my application from Android Studio. My code compiles without errors and the program doesn’t throw any exceptions on Runtime. Nevertheless, when I start my program, it doesn’t respond. My Logcat shows: T…
parsing csv file dealing with empty value java
I am new to java and practicing parsing csv file. I’ve figured out how to parse and use a constructor to create an instance. However, there are empty strings in my csv file, and the console just throw IllegalArgumentException: No enum constant to me. I’ve referred to: enum valueOf IllegalArgumentE…
Difference from running application in IntellJ and running JAR file
I came across a situation when i would run application in intellJ and everything runs smoothly , then i would create a jar using maven install command and try running it manually from command line, the results are the following : Command Line Questions: What is the difference between running Jar and running A…
Tracing a recursive method in Java/Kotlin
In python, I can write a trace function like: and it’d print the recursive trace for any general recursive function beautifully: Is it possible to write a simple similar one in Java/Kotlin? Or is it only doable with AOP or the like? Answer EDIT: formatting does not 100% match yours, but that is easily f…
How to reset autoincrement value after deleting 1 row of column from it, on sqlite java android?
on MYSQLI this method is work on me back then, ALTER TABLE tablename AUTO_INCREMENT = 0, this will reset on last autoincrement position but i don’t know how to do it on SQLITE, so the idea is, i want to delete 1 row column table, and at the same time i want to reset auto increment value to the last
Creating multiple objects using the same instance
I just saw this tutorial creating multiple objects using the same instance by applying the DAO pattern and tried it in a simple console, but I always get this message java.lang.NullPointerException I’m now confused, as far as I know, a constructor can be used once only, and the object will be immutable.…
gradle executable jar can’t include local jar dependencies
SOLVED WaitingDatabase.connect(WaitingDatabase.java:17) (Sorry for bad english.) I have to connect my oracle database, so I downloaded oracle jdbc driver and added in my dependencies. It connected well when I run at intellij, so I built executable jar file with gradle. However, it couldn’t connect to my…
How to create a new object of Public Class
I am a newbie in Java, although I have knowledge of Object Oriented Programming from Python but I’m currently having problem understanding this example on creating public class either combining the …
Reference control by fx:id
I have a calendar screen I have designed for class using JavaFX and Scene Builder. The part where I’ve placed the number is a label and the part that, currently, says “None”, is a button. I want to reference the value in the Label when I select the Button so that I can display the Appointmen…
Java JFrame button organization
How do i create a jframe that organizes the text box and jbuttons, with the textbox on top and a 3 by 4 grid layout of buttons 1-10? This is what I have so far: But that’s where I’m stuck. Okay I should note that I need a for loop to populate 3 by 4 gridlayout. But I don’t know