com.datastax.oss.protocol.internal

Class SegmentBuilder<B,StateT>

java.lang.Object

com.datastax.oss.protocol.internal.SegmentBuilder<B,StateT>

Type Parameters:

B - the binary representation we're manipulating.

StateT - additional information that comes with incoming frames, and must be propagated to outgoing segments (in the Java driver, this is the ChannelPromise that represents the outcome of the write).

public abstract class SegmentBuilder<B,StateT>
extends Object

Abstracts the logic of batching a sequence of outgoing frames into one or more segments in protocol v5 and above.

This class is not thread-safe.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	SegmentBuilder(PrimitiveCodec<B> primitiveCodec, FrameCodec<B> frameCodec)

Method Summary

Modifier and Type	Method and Description
void	addFrame(Frame frame, StateT frameState) Adds a new frame.
void	flush() Signals that we're done adding frames.
protected abstract StateT	mergeStates(List<StateT> frameStates) When we batch multiple frames into one segment, how frame states are combined to form the segment's state.
protected void	onLargeFrameSplit(Frame frame, int frameLength, int sliceCount) Invoked whenever a large frame needs to be split into multiple segments.
protected void	onLastSegmentFlushed(int currentPayloadLength, int currentFrameCount) Invoked whenever flush() was called and it produces one last self-contained segment.
protected void	onSegmentFull(Frame frame, int frameLength, int currentPayloadLength, int currentFrameCount) Invoked whenever the current self-contained segment for small frames is full.
protected void	onSmallFrameAdded(Frame frame, int frameLength, int currentPayloadLength, int currentFrameCount) Invoked whenever a small frame was successfully added to the current self-contained segment, without bringing it over its size limit.
protected abstract void	processSegment(Segment<B> segment, StateT segmentState) What to do whenever a full segment is ready.
protected abstract List<StateT>	splitState(StateT frameState, int sliceCount) When we slice one frame into multiple segments, how the frame's state is split into the slice states.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SegmentBuilder

protected SegmentBuilder(PrimitiveCodec<B> primitiveCodec,
                         FrameCodec<B> frameCodec)

Method Detail

mergeStates

protected abstract StateT mergeStates(List<StateT> frameStates)

When we batch multiple frames into one segment, how frame states are combined to form the segment's state.

splitState

protected abstract List<StateT> splitState(StateT frameState,
                                           int sliceCount)

When we slice one frame into multiple segments, how the frame's state is split into the slice states.

processSegment

protected abstract void processSegment(Segment<B> segment,
                                       StateT segmentState)

What to do whenever a full segment is ready.

addFrame

public void addFrame(Frame frame,
                     StateT frameState)

Adds a new frame. It will be encoded into one or more segments, that will be passed to processSegment(Segment, Object) at some point in the future.

The caller must invoke flush() after the last frame.

flush

public void flush()

Signals that we're done adding frames.

This must be called after adding the last frame, it will possibly trigger the generation of one last segment.

onLargeFrameSplit

protected void onLargeFrameSplit(Frame frame,
                                 int frameLength,
                                 int sliceCount)

Invoked whenever a large frame needs to be split into multiple segments. This is intended for logs in subclasses, the default implementation is empty.

Parameters:

frame - the frame that is being split.

frameLength - the length of that frame in bytes.

sliceCount - the number of slices.

onSegmentFull

protected void onSegmentFull(Frame frame,
                             int frameLength,
                             int currentPayloadLength,
                             int currentFrameCount)

Invoked whenever the current self-contained segment for small frames is full. It's about to get processed, and a new segment will be started. This is intended for logs in subclasses, the default implementation is empty.

Parameters:

frame - the frame that triggered this action. Note that it will not be included in the current segment (since adding it would have brought the segment over its maximum length).

frameLength - the length of that frame in bytes.

currentPayloadLength - the length of the segment's payload in bytes.

currentFrameCount - the number of frames in the segment.

onSmallFrameAdded

protected void onSmallFrameAdded(Frame frame,
                                 int frameLength,
                                 int currentPayloadLength,
                                 int currentFrameCount)

Invoked whenever a small frame was successfully added to the current self-contained segment, without bringing it over its size limit. This is intended for logs in subclasses, the default implementation is empty.

Parameters:

frame - the frame.

frameLength - the length of that frame in bytes.

currentPayloadLength - the new total length of the segment's payload, after the frame was added.

currentFrameCount - the total number of frames in the payload, after the frame was added.

onLastSegmentFlushed

protected void onLastSegmentFlushed(int currentPayloadLength,
                                    int currentFrameCount)

Invoked whenever flush() was called and it produces one last self-contained segment. This is intended for logs in subclasses, the default implementation is empty.

Parameters:

currentPayloadLength - the length of the segment's payload in bytes.

currentFrameCount - the number of frames in the segment.