[Doc] Correct misleading buffer comment in CommitLog#doAppend

[fuyou001]

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Documentation Related

In store/src/main/java/org/apache/rocketmq/store/CommitLog.java, DefaultAppendMessageCallback#doAppend(...) currently contains:

// Write messages to the queue buffer
byteBuffer.put(preEncodeBuffer);

The comment is misleading. The byteBuffer is the destination buffer supplied by DefaultMappedFile#appendMessagesInner(...) for appending the encoded message through the CommitLog write path. Depending on configuration, it can be backed by the mapped byte buffer, the transient write buffer, or a shared staging buffer used by the writeWithoutMmap path. It is not a queue or ConsumeQueue buffer.

The comment should describe appending the encoded message to the current CommitLog buffer. This is a documentation-only correction and does not change runtime behavior.

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• Yes I am willing to submit a PR!

[RockteMQ-AI]

Issue Evaluation

Category: documentation | Status: Confirmed

Verified against the codebase. At store/src/main/java/org/apache/rocketmq/store/CommitLog.java:2095, the comment // Write messages to the queue buffer is indeed misleading — byteBuffer is the destination buffer supplied by DefaultMappedFile#appendMessagesInner, which can be backed by the mapped byte buffer, transient write buffer, or shared staging buffer depending on configuration. It is not a queue/ConsumeQueue buffer.

This is a straightforward documentation-only correction with no runtime impact. The fix is valid.

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Automated evaluation by RockteMQ-AI