Your API latency spikes and Hikari logs connection leak detection. What is your checklist?
PICTURE THIS: A REST CALL
Simple meaning
Find requests that borrow a connection and never return it: missing try-with-resources, a long HTTP call inside @Transactional, or Open Session in View.
WHY — Connection pooling instead of guessing?
Why interviewers care about Connection pooling:
people who only read docs from people who shipped.
and tied to Backend work.
Name the idea, why it exists, then one short example.
End with when you use it and one common pitfall.
STEPS — What happens step by step?
Before you speak the answer, walk the interviewer through these steps:
- 1Find requests that borrow
a connection and never return it: missing try-with-resources, a long HTTP call inside @Transactional, or Open Session in View.
- 2Check pool size versus
threads and whether a slow query holds connections.
- 3leakDetectionThreshold helps you get
a stack trace of the borrower.
- 4Give an example
One tiny concrete case you can say aloud.
- 5Common mistake
What juniors usually get wrong.
- 6Close
When you pick this over the alternative.
EXAMPLE — See it in action
Here's a short line you can speak, broken into clear beats:
Note: Adapt this scaffold to your own project — keep it under 60–90 seconds.
Key takeaway
Find requests that borrow a connection and never return it: missing try-with-resources, a long HTTP call inside @Transactional, or Open Session in View. Check pool size versus threads and whether a slow query holds connections.