hi Chain
> ? - 1 byte value 0x3c
This magic byte represents the size of the following 'Array of API keys.'
We need to know the size of the array to determine how many elements must
be read from the network.
Here's a snippet demonstrating how the size is used.
```
int arrayLength = _readable.readUnsignedVarint() - 1;
ApiVersionCollection newCollection = new ApiVersionCollection(arrayLength);
for (int i = 0; i < arrayLength; i++) {
newCollection.add(new ApiVersion(_readable, _version));
}
this.apiKeys = newCollection;
```
Best,
Chia-Ping
Chain Head <[email protected]> 於 2024年10月28日 週一 上午12:20寫道：
> Hello,
> I set-up a simple Java client to publish a sample message to Kafka broker.
> I can see API Versions request v3 and response messages. I am able to map
> all the bytes as described here (
> https://kafka.apache.org/protocol.html#The_Messages_ApiVersions) for API
> Versions request and response except for 1 byte as shown below.
>
> - Length - INT32
> - Correlation ID - INT32
> - Error code - INT16
> - ? - 1 byte value 0x3c
> - Array of API keys, supported versions and tagged fields
> - Throttle - INT32
> - Tagged fields.
>
> Can you please help me understand?
>
> Thanks.
>
