com.twitter.distributedlog

Class LogRecordSet

java.lang.Object

com.twitter.distributedlog.LogRecordSet

public class LogRecordSet
extends Object

A set of LogRecords.

 Structure:
 Bytes 0  -  4                : Metadata (version + flags)
 Bytes 4  - 7                 : Number of Records
 Bytes 8  - 11                : Original Payload Length
 Bytes 12 - 15                : Actual Payload Length
 Bytes 16 - 16+length-1       : Payload
 ------------------------------------------------------

 Metadata: Version and Flags // 32 Bits
 --------------------------------------
 0 ... 0 0 0 0 0
             |_|
              |
    Compression Codec: // 2 Bits (Least significant)
    -----------------
    00        : No Compression
    01        : LZ4 Compression
    10        : Unused
    11        : Unused

 

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	LogRecordSet.Reader Reader to read LogRecords from this record set.
static interface	LogRecordSet.Writer Writer to append LogRecords to LogRecordSet.

Field Summary

Fields

Modifier and Type	Field and Description
static int	HEADER_LEN

Constructor Summary

Constructors

Constructor and Description
LogRecordSet()

Method Summary

Methods

Modifier and Type	Method and Description
static LogRecordSet.Writer	newWriter(int initialBufferSize, CompressionCodec.Type codec)
static int	numRecords(byte[] data)
static int	numRecords(LogRecord record)
static LogRecordSet.Reader	of(LogRecordWithDLSN record)

Methods inherited from class java.lang.Object

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

Field Detail

HEADER_LEN

public static final int HEADER_LEN

See Also:

Constant Field Values

Constructor Detail

LogRecordSet

public LogRecordSet()

Method Detail

numRecords

public static int numRecords(LogRecord record)
                      throws IOException

Throws:

IOException

numRecords

public static int numRecords(byte[] data)
                      throws IOException

Throws:

IOException

newWriter

public static LogRecordSet.Writer newWriter(int initialBufferSize,
                            CompressionCodec.Type codec)

of

public static LogRecordSet.Reader of(LogRecordWithDLSN record)
                              throws IOException

Throws:

IOException