[Troubleshooting] QueryDSL StackOverflowError Investigation
I’m sharing about a Querydsl StackOverflow issue I encountered at work. Problem Occurrence As always, the problem starts with a Slack message. As soon as I received the message, I couldn’t help but react with “huh?” StackOverflow? Was there recursively implemented code in the server? What is StackOv...
March 15, 2024
[Troubleshooting] Failed Graceful Shutdown During Kubernetes Pod Scale In, Journey to Find Lost Async Logic
I’m sharing about a failed Graceful Shutdown issue I encountered at work. Problem Occurrence Usually, I encounter exceptions and problem situations through Slack quite often. Today, I encountered a problem differently than usual. This problem started with a back office user’s inquiry. “I think one p...
February 9, 2024
Journey to Resolving HikariCP Deadlock When Using JPA and MyBatis Together (feat. OSIV)
I’m sharing an issue related to HikariCP Deadlock that I encountered at work. Problem Occurrence As always, the issue starts with a Slack message. Excerpt from Stack trace Caused by: java.sql.SQLTransientConnectionException: HikariPool-1 - Connection is not available, request timed out after 30008ms...
January 9, 2024
Spring Batch Job Concurrent Registration Deadlock Issue (Deadlock accessing creating a job on sqlserver when multiple jobs start at once)
I’d like to share a Spring Batch-related issue I encountered at work. Problem Occurrence The issue started with an error message in Slack. It was a stack trace indicating that a Deadlock had occurred on our company’s Batch server. Naturally, since Deadlock could severely impact the service, I immedi...
November 20, 2023
Creating a Common Excel Download Utility Class Using Java POI
It’s nothing grand, but I’d like to share an experience I had at work a few months ago. It started with inquiries from end users, namely my coworkers, who use the back-office system internally. The inquiry was as follows: Excel download doesn’t work or becomes strange when the row count exceeds a ce...
November 19, 2023
Review of Auto-Trading System Built with Spring Batch
It’s not grand content, but I want to share a personal experience I had a few months ago. https://github.com/12OneTwo12/auto-trading This article doesn’t describe how to implement it. If you want to see the code, please enter the github link above. Also, I think the auto-trading system I made doesn’...
October 24, 2023