org.apache.kafka.common.record
Class MemoryRecords

java.lang.Object
  org.apache.kafka.common.record.MemoryRecords

All Implemented Interfaces:

java.lang.Iterable<LogEntry>, Records

public class MemoryRecords
extends java.lang.Object
implements Records

A Records implementation backed by a ByteBuffer.

Nested Class Summary

static class

MemoryRecords.RecordsIterator

Field Summary

Fields inherited from interface org.apache.kafka.common.record.Records

LOG_OVERHEAD, OFFSET_LENGTH, SIZE_LENGTH

Method Summary

void	append(long offset, byte[] key, byte[] value) Append a new record and offset to the buffer
void	append(long offset, Record record) Append the given record and offset to the buffer
java.nio.ByteBuffer	buffer() Get the byte buffer that backs this records instance
int	capacity() Return the capacity of the buffer
void	close() Close this batch for no more appends
double	compressionRate() The compression rate of this record set
static MemoryRecords	emptyRecords(java.nio.ByteBuffer buffer, CompressionType type)
static MemoryRecords	emptyRecords(java.nio.ByteBuffer buffer, CompressionType type, int capacity)
boolean	hasRoomFor(byte[] key, byte[] value) Check if we have room for a new record containing the given key/value pair Note that the return value is based on the estimate of the bytes written to the compressor, which may not be accurate if compression is really used.
boolean	isFull()
static MemoryRecords	iterableRecords(java.nio.ByteBuffer buffer)
java.util.Iterator<LogEntry>	iterator()
int	sizeInBytes() The size of this record set
int	writeTo(java.nio.channels.GatheringByteChannel channel) Write the records in this set to the given channel

Methods inherited from class java.lang.Object

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

Method Detail

emptyRecords

public static MemoryRecords emptyRecords(java.nio.ByteBuffer buffer,
                                         CompressionType type,
                                         int capacity)

emptyRecords

public static MemoryRecords emptyRecords(java.nio.ByteBuffer buffer,
                                         CompressionType type)

iterableRecords

public static MemoryRecords iterableRecords(java.nio.ByteBuffer buffer)

append

public void append(long offset,
                   Record record)

Append the given record and offset to the buffer

append

public void append(long offset,
                   byte[] key,
                   byte[] value)

Append a new record and offset to the buffer

hasRoomFor

public boolean hasRoomFor(byte[] key,
                          byte[] value)

Check if we have room for a new record containing the given key/value pair Note that the return value is based on the estimate of the bytes written to the compressor, which may not be accurate if compression is really used. When this happens, the following append may cause dynamic buffer re-allocation in the underlying byte buffer stream. Also note that besides the records' capacity, there is also a size limit for the batch. This size limit may be smaller than the capacity (e.g. when appending a single message whose size is larger than the batch size, the capacity will be the message size, but the size limit will still be the batch size), and when the records' size has exceed this limit we also mark this record as full.

isFull

public boolean isFull()

close

public void close()

Close this batch for no more appends

writeTo

public int writeTo(java.nio.channels.GatheringByteChannel channel)
            throws java.io.IOException

Write the records in this set to the given channel

Specified by:

writeTo in interface Records

Parameters:

channel - The channel to write to

Returns:

The number of bytes written

Throws:

java.io.IOException - If the write fails.

sizeInBytes

public int sizeInBytes()

The size of this record set

Specified by:

sizeInBytes in interface Records

compressionRate

public double compressionRate()

The compression rate of this record set

capacity

public int capacity()

Return the capacity of the buffer

buffer

public java.nio.ByteBuffer buffer()

Get the byte buffer that backs this records instance

iterator

public java.util.Iterator<LogEntry> iterator()

Specified by:

iterator in interface java.lang.Iterable<LogEntry>