org.apache.hadoop.hive.serde2

Class WriteBuffers

java.lang.Object

org.apache.hadoop.hive.serde2.WriteBuffers

All Implemented Interfaces:

ByteStream.RandomAccessOutput

public final class WriteBuffers
extends Object
implements ByteStream.RandomAccessOutput

The structure storing arbitrary amount of data as a set of fixed-size byte buffers. Maintains read and write pointers for convenient single-threaded writing/reading.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	WriteBuffers.ByteSegmentRef The class representing a segment of bytes in the buffer.
static class	WriteBuffers.Position

Constructor Summary

Constructors

Constructor and Description
WriteBuffers(int wbSize, long maxSize)

Method Summary

Methods

Modifier and Type	Method and Description
void	clear()
void	getByteSegmentRefToCurrent(WriteBuffers.ByteSegmentRef byteSegmentRef, int length, WriteBuffers.Position readPos)
int	getLength()
long	getReadPoint()
long	getReadPoint(WriteBuffers.Position readPos)
WriteBuffers.Position	getReadPosition()
long	getWritePoint()
int	hashCode(byte[] key, int offset, int length)
int	hashCode(long offset, int length)
int	hashCode(long offset, int length, WriteBuffers.Position readPos)
boolean	isEqual(byte[] left, int leftOffset, int leftLength, long rightOffset, int rightLength) Compares part of the buffer with a part of an external byte array.
boolean	isEqual(byte[] left, int leftLength, long rightOffset, int rightLength) Compares part of the buffer with a part of an external byte array.
boolean	isEqual(long leftOffset, int leftLength, long rightOffset, int rightLength) Compares two parts of the buffer with each other.
static int	murmurHash(byte[] data, int offset, int length)
void	populateValue(WriteBuffers.ByteSegmentRef value) Changes the byte segment reference from being a reference to global buffer to the one with a self-contained byte array.
int	readInt(long offset)
long	readNByteLong(long offset, int bytes)
long	readNByteLong(long offset, int bytes, WriteBuffers.Position readPos)
int	readVInt()
int	readVInt(WriteBuffers.Position readPos)
long	readVLong()
long	readVLong(WriteBuffers.Position readPos)
void	reserve(int byteCount)
void	seal()
void	setReadPoint(long offset)
void	setReadPoint(long offset, WriteBuffers.Position readPos)
void	setWritePoint(long offset)
long	size() Write buffer size
void	skipVLong()
void	skipVLong(WriteBuffers.Position readPos)
void	write(byte[] b)
void	write(byte[] b, int off, int len)
void	write(int b)
void	writeByte(long offset, byte value)
void	writeBytes(long offset, int length) Reads some bytes from the buffer and writes them again at current write point.
void	writeFiveByteULong(long offset, long v)
void	writeInt(long offset, int v)
void	writeVInt(int value)
void	writeVLong(long value)

Methods inherited from class java.lang.Object

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

Constructor Detail

WriteBuffers

public WriteBuffers(int wbSize,
            long maxSize)

Method Detail

readVInt

public int readVInt()

readVInt

public int readVInt(WriteBuffers.Position readPos)

readVLong

public long readVLong()

readVLong

public long readVLong(WriteBuffers.Position readPos)

skipVLong

public void skipVLong()

skipVLong

public void skipVLong(WriteBuffers.Position readPos)

setReadPoint

public void setReadPoint(long offset)

setReadPoint

public void setReadPoint(long offset,
                WriteBuffers.Position readPos)

hashCode

public int hashCode(long offset,
           int length)

hashCode

public int hashCode(long offset,
           int length,
           WriteBuffers.Position readPos)

hashCode

public int hashCode(byte[] key,
           int offset,
           int length)

reserve

public void reserve(int byteCount)

Specified by:

reserve in interface ByteStream.RandomAccessOutput

setWritePoint

public void setWritePoint(long offset)

write

public void write(int b)

Specified by:

write in interface ByteStream.RandomAccessOutput

write

public void write(byte[] b)

Specified by:

write in interface ByteStream.RandomAccessOutput

write

public void write(byte[] b,
         int off,
         int len)

Specified by:

write in interface ByteStream.RandomAccessOutput

getLength

public int getLength()

Specified by:

getLength in interface ByteStream.RandomAccessOutput

isEqual

public boolean isEqual(long leftOffset,
              int leftLength,
              long rightOffset,
              int rightLength)

Compares two parts of the buffer with each other. Does not modify readPoint.

isEqual

public boolean isEqual(byte[] left,
              int leftLength,
              long rightOffset,
              int rightLength)

Compares part of the buffer with a part of an external byte array. Does not modify readPoint.

isEqual

public boolean isEqual(byte[] left,
              int leftOffset,
              int leftLength,
              long rightOffset,
              int rightLength)

Compares part of the buffer with a part of an external byte array. Does not modify readPoint.

clear

public void clear()

getWritePoint

public long getWritePoint()

getReadPoint

public long getReadPoint()

getReadPoint

public long getReadPoint(WriteBuffers.Position readPos)

getByteSegmentRefToCurrent

public void getByteSegmentRefToCurrent(WriteBuffers.ByteSegmentRef byteSegmentRef,
                              int length,
                              WriteBuffers.Position readPos)

writeVInt

public void writeVInt(int value)

writeVLong

public void writeVLong(long value)

writeBytes

public void writeBytes(long offset,
              int length)

Reads some bytes from the buffer and writes them again at current write point.

populateValue

public void populateValue(WriteBuffers.ByteSegmentRef value)

Changes the byte segment reference from being a reference to global buffer to the one with a self-contained byte array. The byte array will either be one of the internal ones, or a copy of data if the original reference pointed to a data spanning multiple internal buffers.

seal

public void seal()

readNByteLong

public long readNByteLong(long offset,
                 int bytes)

readNByteLong

public long readNByteLong(long offset,
                 int bytes,
                 WriteBuffers.Position readPos)

writeFiveByteULong

public void writeFiveByteULong(long offset,
                      long v)

readInt

public int readInt(long offset)

writeInt

public void writeInt(long offset,
            int v)

Specified by:

writeInt in interface ByteStream.RandomAccessOutput

writeByte

public void writeByte(long offset,
             byte value)

Specified by:

writeByte in interface ByteStream.RandomAccessOutput

murmurHash

public static int murmurHash(byte[] data,
             int offset,
             int length)

size

public long size()

Write buffer size

Returns:

write buffer size

getReadPosition

public WriteBuffers.Position getReadPosition()