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Java / Java 21 Coding Standards Interview Questions

What are the types of comments recommended in Java style guides?

Java style guides recognize three categories of comments, each with a distinct purpose:

TypePurpose
Javadoc (/** ... */)Documents the public contract of a class or method for external callers and generated API docs.
Block comment (/* ... */)Explains a non-obvious algorithm or a workaround, placed just above the code it describes.
Line comment (//)Adds a short clarifying note on or above a single statement.

Standards discourage comments that restate what the code already says, such as // increment i above i++, and instead push authors toward naming the code clearly enough that a comment explaining "what" is rarely needed - comments are reserved for explaining "why".

Which comment style is intended to document a public API contract for external callers?
Style guides generally discourage comments that:

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