org.apache.hadoop.hive.ql.exec.vector.mapjoin.fast

Class VectorMapJoinFastBytesHashSetStore

java.lang.Object

org.apache.hadoop.hive.ql.exec.vector.mapjoin.fast.VectorMapJoinFastBytesHashSetStore

All Implemented Interfaces:

MemoryEstimate

public class VectorMapJoinFastBytesHashSetStore
extends Object
implements MemoryEstimate

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	VectorMapJoinFastBytesHashSetStore.HashSetResult A hash set result for the key.

Constructor Summary

Constructors

Constructor and Description
VectorMapJoinFastBytesHashSetStore(int writeBuffersSize)

Method Summary

Modifier and Type	Method and Description
long	add(long partialHashCode, byte[] keyBytes, int keyStart, int keyLength) Two 64-bit long result is the key and value reference.
long	getEstimatedMemorySize()
WriteBuffers	getWriteBuffers() A store for a bytes key for a hash set in memory.

Methods inherited from class java.lang.Object

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

Constructor Detail

VectorMapJoinFastBytesHashSetStore

public VectorMapJoinFastBytesHashSetStore(int writeBuffersSize)

Method Detail

getWriteBuffers

public WriteBuffers getWriteBuffers()

A store for a bytes key for a hash set in memory. The memory is a "infinite" byte array as a WriteBuffers object. We give the client (e.g. hash set logic) a 64-bit key and count reference to keep that has the offset within the "infinite" byte array of the key. The 64 bits includes about half of the upper hash code to help during matching. We optimize the common case when the key length is short and store that information in the 64 bit reference. Cases: 1) One element when key and is small (and stored in the reference word): Key and Value Reference | | absoluteOffset | | v <Key Bytes> KEY 2) One element, general: shows optional big key length. Key and Value Reference | | absoluteOffset | | v [Big Key Length] <Key Bytes> optional KEY

add

public long add(long partialHashCode,
                byte[] keyBytes,
                int keyStart,
                int keyLength)

Two 64-bit long result is the key and value reference.

Parameters:

partialHashCode -

keyBytes -

keyStart -

keyLength -

getEstimatedMemorySize

public long getEstimatedMemorySize()

Specified by:

getEstimatedMemorySize in interface MemoryEstimate