I have a method overload that goes as follows: My question is there a way to condense the solution to have one method that takes into account N-Dimensional Arrays. The code runs fine like this however, I would like to know what Java techniques can help account for the increase in dimensions. I would like to a…
Tag: java
Make sure to call FirebaseApp.initializeApp(Context) first.Default FirebaseApp is not initialized in this process
I am facing this issue and seen some answers on this site but did not get any proper solution. I have used previous version of Firebase which works fine but when I try to upgrade using Upgradation and update Firebase class to DatabaseReference it shows error and not working. Error Screenshot My Module app is …
Spring Boot, using oracle-ldap url through ssh tunnel on local machine
There are 3 machines: local -> some remote server -> oracle db server (via ldap) I want to set up datasource connection (in my spring boot app) to the oracle db. There is no direct connectivity between local machine and the one with oracle db. So, i’m using the ssh tunnel through remote server: ss…
How to downgrade JDK?
Currently my Java version is 17. Neo4j requires me to install Java 11 or OpenJDK 11, or else it will give the error java.lang.IllegalAccessException: module java.base does not open java.nio to unnamed module @1817d444. I guess I need to downgrade to JDK 11. Java Platform, Standard Edition 11 Reference Impleme…
JPA repository return one item from db but there are multiple item in the db
I have the following function in my repository When I use this function in the controller I got back one User. For example, if I have a String “John” and I call the repo function with that string I got back “John Doe” but I also have “John Doe Jr” in the db and I need him t…
endpoint for authentication with spring security
I wanna create custom endpoint for login. It works fine when password and username are correct but returns 200 and login form instead 401 for incorrect data. public class SecurityConfiguration extends WebSecurityConfigurerAdapter { private final UserDetailsService userDetailsService; } Answer Try something li…
Java mutable object to causing nullpointer exception
I have the following DTO and I pass the objects to the ArrayLists to prevent objects to be changed and fix the SonarQube error as “Message: Store a copy of allergenInfoList”, etc. However, this approach requires null check and it makes my code ugly as shown below: So, is there any better approach …
Java Swing Application Window – Second Form showing empty
The first class or JFrame that displays just fine And now my second class.. I’m sorry I’m a complete noob, when I run the debugger it looks like Options Menu is constructing correctly, but then it just displays as the minimize, full screen and exit button and nothing else. It will also run perfect…
How to filter an array of objects by month and year – Java
I’m new at Java and I have a question. I have this array of objects: That contains this: I would like to know how can I filter this array by month and year. A first example would be filter the array by month 10 and year 2021. Any suggestion ? Answer You can use the Stream API to do it
what’s the benefit of using Serviceability Agent when debuging HotspotJVM under linux?
in linux, the Hotspot Serviceability Agent is implemented by ptrace, which will stop the debugee process. Since it has side effect on target JVM, why not just simply attach to that JVM? If SA has no impact on target JVM, then it’s very useful. But the truth is not. So I’m wonder what’s the m…