Moderate Spring Question 211 of 226

What is dependency injection in Spring?

Java Specialist · Speak this in 60–90 seconds · Faridabad & Delhi NCR

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Simple meaning

Spring creates objects and supplies their dependencies instead of new inside business code.

WHY — Spring instead of guessing?

Why interviewers care about Spring:

Spring questions separate people

who only read docs from people who shipped.

Keep it short, concrete,

and tied to Backend work.

Stay structured

Name the idea, why it exists, then one short example.

Close cleanly

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:

1
Spring creates objects and
supplies their dependencies instead of new inside business code.
2
Constructor injection is preferred
because dependencies are clear and testable.
3
How it works
It keeps services loosely coupled.
4
Give an example
One tiny concrete case you can say aloud.
5
Common mistake
What juniors usually get wrong.
6
Close
When you pick this over the alternative.

EXAMPLE — See it in action

Here's a short line you can speak, broken into clear beats:

Say this line

“Constructor injection is preferred because dependencies are clear and testable.”

Break into beats

Constructorinjectionispreferredbecausedependencies

Speaking order

2987408337471632900

Note: Adapt this scaffold to your own project — keep it under 60–90 seconds.

Key takeaway

Spring creates objects and supplies their dependencies instead of new inside business code. Constructor injection is preferred because dependencies are clear and testable.