A bean stores per-request user data in a field, but it is singleton scoped. What is the biggest risk?

Question

A bean stores per-request user data in a field, but it is singleton scoped. What is the biggest risk?

Option A — Correct answer

State can leak across requests or threads

Singleton beans are shared by default.

Option B

The bean cannot be autowired

Option C

The JVM cannot compile annotations

Option D

The class becomes abstract automatically

Explanation

Singleton beans are shared, so mutable request-specific state can leak between users or threads.

Quiz: Spring Core